HomeDocs changes
Documentation changes
What the docs quietly changed.
Anthropic's published documentation, fetched on a schedule and diffed against the last copy. Every edit dated, including the ones that never made a release note.
Last poll read all 4 cleanly: Claude Code CLI, Claude Developer Platform, Claude Documentation, Model Context Protocol. A date here is when this site noticed, not when Anthropic edited.
Claude Developer Platform
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767 changed this week · last read 24 Oct 2026
Claude Code CLI
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146 changed this week · last read 24 Oct 2026
Claude Documentation
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69 changed this week · last read 24 Oct 2026
Model Context Protocol
357pages tracked
171 changed this week · last read 23 Oct 2026
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models/sonnet-4-5/overview
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models/sonnet-4-5/overview
description: "Claude Sonnet 4.5 reference: lifecycle status, model IDs on every platform, context window, output limits, pricing, and migration resources. Claude Sonnet 4.5 is a le
description: "Claude Sonnet 4.5 reference: lifecycle status, model IDs on every platform, context window, output limits, pricing, and migration resources. Claude Sonnet 4.5 is a le
Although Claude Sonnet 4.5 is still available, you should consider migrating to Claude Sonnet 5 for improved performance. [See Claude Sonnet 5](https://platform.claude.com/docs/en/
Although Claude Sonnet 4.5 is still available, you should consider migrating to Claude Sonnet 5.5 for improved performance. [See Claude Sonnet 5.5](https://platform.claude.com/docs
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
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models/overview
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| Feature | Claude Fable 5.1
| :-------------------------------------------------------------------------------------------------------- | :---------------------------------------------------------------------
| Description | For demanding reasoning and long-horizon agentic work
| Model page | [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-
| Comparative latency | Slower
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models/opus-5/overview
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| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
| **Claude Opus 5** (this model) | 1M | 128K | $5 / $25 | Adaptive | `high` | May 2026
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models/opus-5-5/overview
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models/opus-5-5/overview
| Model | Context | Max output | Price / MTok | Latency | Thinking | Default effort | Knowl
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------- | :------------------- | :------------- | :----
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | `high` | Jun 2
| **Claude Opus 5.5** (this model) | 1M | 128K | $4 / $20 | Moderate | Adaptive (always on) | `medium` | Jun 2
| [Claude Sonnet 5](https://platform.claude.com/docs/en/models/sonnet-5/overview) | 1M | 128K | $2 / $10 | Fast | Adaptive | `high` | Jan 2
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models/opus-4-8/overview
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models/opus-4-8/overview
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
| **Claude Opus 4.8** (this model) | 1M | 128K | $5 / $25 | Adaptive | `high` | Jan 2026
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models/opus-4-7/overview
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models/opus-4-7/overview
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
| **Claude Opus 4.7** (this model) | 1M | 128K | $5 / $25 | Adaptive | `high` | Jan 2026
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models/opus-4-6/overview
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models/opus-4-6/overview
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowle
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :----------------------------- | :------------- | :-----
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 20
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 20
| **Claude Opus 4.6** (this model) | 1M | 128K | $5 / $25 | Adaptive (extended deprecated) | `high` | May 20
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models/opus-4-5/overview
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| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
| **Claude Opus 4.5** (this model) | 200K | 64K | $5 / $25 | Extended | `high` | May 2025
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models/mythos-5/overview
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models/mythos-5/overview
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| **Claude Mythos 5** (this model) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jan 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
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models/mythos-5-1/overview
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models/mythos-5-1/overview
| Model | Context | Max output | Price / MTok | Latency | Thinking | Default effort | Knowl
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------- | :------------------- | :------------- | :----
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | `high` | Jun 2
| **Claude Mythos 5.1** (this model) | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | `high` | Jun 2
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Moderate | Adaptive (always on) | `medium` | Jun 2
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models/haiku-4-5/overview
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models/haiku-4-5/overview
| Model | Context | Max output | Price / MTok | Latency | Thinking | Default effort | Knowl
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------- | :------------------- | :------------- | :----
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | `high` | Jun 2
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Moderate | Adaptive (always on) | `medium` | Jun 2
| [Claude Sonnet 5](https://platform.claude.com/docs/en/models/sonnet-5/overview) | 1M | 128K | $2 / $10 | Fast | Adaptive | `high` | Jan 2
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models/fable-5/overview
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models/fable-5/overview
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------------------- | :------------- | :---------------
| [Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026
| **Claude Fable 5** (this model) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jan 2026
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026
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models/fable-5-1/overview
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| Model | Context | Max output | Price / MTok | Latency | Thinking | Default effort | Knowl
| :-------------------------------------------------------------------------------- | :------ | :--------- | :----------- | :------- | :------------------- | :------------- | :----
| **Claude Fable 5.1** (this model) | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | `high` | Jun 2
| [Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Moderate | Adaptive (always on) | `medium` | Jun 2
| [Claude Sonnet 5](https://platform.claude.com/docs/en/models/sonnet-5/overview) | 1M | 128K | $2 / $10 | Fast | Adaptive | `high` | Jan 2
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managed-agents/reference
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managed-agents/reference
| Type | Description
| ---------------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------
| `system.message` | Append privileged system-level context that applies to the accompanying turn and all subsequent turns. Supported on Claude Fable 5.1, Claude Mythos 5.1, Cl
| Type | Description
| ---------------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------
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managed-agents/events-and-streaming
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managed-agents/events-and-streaming
`system.message` is supported by Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opus 5, and Claude Opus 4.8. If the agent's primary
`system.message` is supported by Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, and Claude Sonnet 5.5. If
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intro
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intro
* [Claude Sonnet 5](https://platform.claude.com/docs/en/models/sonnet-5/overview) (`claude-sonnet-5`) — *The best combination of speed and intelligence* — Everyday tasks · Writing
* [Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/overview) (`claude-sonnet-5-5`) — New — *The best combination of speed and intelligence* — Everyday task
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home
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home
* [Claude Sonnet 5](https://platform.claude.com/docs/en/models/sonnet-5/overview) (`claude-sonnet-5`) — *The best combination of speed and intelligence* — Everyday tasks · Writ
* [Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/overview) (`claude-sonnet-5-5`) — New — *The best combination of speed and intelligence* — Everyday
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claude_api_primer
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claude_api_primer
Smart model: Claude Sonnet 5: claude-sonnet-5
Smart model: Claude Sonnet 5.5: claude-sonnet-5-5
Previous Sonnet model: Claude Sonnet 5: claude-sonnet-5
* Claude Sonnet 5.5 (`claude-sonnet-5-5`, adaptive thinking only, on by default)
On Claude Opus 5.5, Claude Fable 5.1, and Claude Mythos 5.1, `any` and `tool` return a 400 error. Leave `tool_choice` at `auto` and set `"strict": true` on the tool definition to g
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build-with-claude/working-with-messages
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build-with-claude/working-with-messages
On Claude Fable 5.1, [Claude Mythos 5.1](https://anthropic.com/glasswing), Claude Fable 5, [Claude Mythos 5](https://anthropic.com/glasswing), Claude Opus 5.5, Claude Opus 4.8, and
On Claude Fable 5.1, [Claude Mythos 5.1](https://anthropic.com/glasswing), Claude Fable 5, [Claude Mythos 5](https://anthropic.com/glasswing), Claude Opus 5.5, Claude Opus 4.8, Cla
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build-with-claude/thinking-troubleshooting
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The table lists what each model supports, what it defaults to, and which `thinking.type` values it rejects with a 400 error; any value not listed as rejected is accepted.
The table lists what each model supports, what it defaults to, and which `thinking.type` values it rejects with a 400 error; any value not listed as rejected is accepted. Only Clau
| Claude Sonnet 5.5 | Adaptive, `between_tools`3 | On | `"enabled"`, `"disabled"` |
*2 Claude Opus 5 accepts `"disabled"` at [effort](https://platform.claude.com/docs/en/build-with-claude/effort) `high` or below; combining it with effort `xhigh` or `max` returns a
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build-with-claude/thinking
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build-with-claude/thinking
| Model | No `thinking` field | `"adaptive"` | `"enabled"` with `budget_tokens` | `"disabled"` |
| --------------------- | ------------------- | ----------------- | -------------------------------- | -------------------------------------- |
| Claude Opus 5.5 | Adaptive thinking | Adaptive thinking | 400 error | 400 error |
| Claude Fable 5.1 | Adaptive thinking | Adaptive thinking | 400 error | 400 error |
| Claude Mythos 5.1 | Adaptive thinking | Adaptive thinking | 400 error | 400 error |
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build-with-claude/task-budgets
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- claude-sonnet-5-5
| Claude Sonnet 5.5 | Beta (set `task-budgets-2026-03-13` header) |
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build-with-claude/structured-outputs
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build-with-claude/structured-outputs
- claude-sonnet-5-5
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build-with-claude/refusals-and-fallback
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build-with-claude/refusals-and-fallback
description: How Claude Fable and Claude Opus models return classifier refusals and how to retry refused requests on a fallback model.
description: How Claude Fable models, Claude Opus models, and Claude Sonnet 5.5 return classifier refusals and how to retry refused requests on a fallback model.
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, and Claude Opus 5 include safety classifiers that can decline a request. When that happens, you receive a normal response, not an
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, and Claude Sonnet 5.5 include safety classifiers that can decline a request. When that happens, you receive a norm
* The request must be valid as a direct request to every model named. If a fallback model does not support a feature the request uses, the API rejects the request up front.
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build-with-claude/prompt-engineering/claude-prompting-best-practices
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build-with-claude/prompt-engineering/claude-prompting-best-practices
This is the reference for prompt engineering with current Claude models, including Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opu
This is the reference for prompt engineering with current Claude models, including Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opu
For an overview of model capabilities, see the [models overview](https://platform.claude.com/docs/en/models/overview). For Claude Fable 5.1 capabilities and API changes, see [Wha
For an overview of model capabilities, see the [models overview](https://platform.claude.com/docs/en/models/overview). For Claude Fable 5.1 capabilities and API changes, see [Wha
| Model | Guide | What'
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build-with-claude/prompt-caching
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| Claude Sonnet 5.5 | $2 / MTok | $2.50 / MTok | $4 /
* 512 tokens for Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, Claude Opus 5, Claude Fable 5, and [Claude Mythos 5](https://anthropic.com/glasswing)
* 512 tokens for Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Fable 5, and [Claude Mythos 5](https://anthropic.com/glasswing)
| **Dropped thinking blocks** | ✓ | ✓ | ✘ | When the API drops a Claude Fable 5.1, Claude Mythos 5.1, or Claude
| **Dropped thinking blocks** | ✓ | ✓ | ✘ | When the API drops a Claude Fable 5.1, Claude Mythos 5.1, Claude Op
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build-with-claude/preserved-thinking
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build-with-claude/preserved-thinking
Claude Sonnet 5.5's thinking blocks are also tied to the account that produced them. See [Thinking blocks stay with the account that produced them](https://platform.claude.com/docs
Also check your integration if it sends Claude Sonnet 5.5 thinking blocks from one account in a request made by a different account. See [Thinking blocks stay with the account that
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build-with-claude/mid-conversation-system-messages
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build-with-claude/mid-conversation-system-messages
This feature is available on Claude Fable 5.1, [Claude Mythos 5.1](https://anthropic.com/glasswing), Claude Fable 5, [Claude Mythos 5](https://anthropic.com/glasswing), Claude Op
This feature is available on Claude Fable 5.1, [Claude Mythos 5.1](https://anthropic.com/glasswing), Claude Fable 5, [Claude Mythos 5](https://anthropic.com/glasswing), Claude Op
A `role: "system"` message can also carry `output_config.effort` to change the [effort](https://platform.claude.com/docs/en/build-with-claude/effort) level from the next `user` tur
A `role: "system"` message can also carry `output_config.effort` to change the [effort](https://platform.claude.com/docs/en/build-with-claude/effort) level from the next `user` tur
The main use is a per-turn reminder in a tool loop. Append the reminder after the `tool_result` message each time you want the model to see it, and leave every earlier copy where i
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build-with-claude/handling-stop-reasons
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A refused request on Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, or Claude Opus 5 can usually be served by retrying on another Claude model. [Refusals and fallback](https://
A refused request on Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, or Claude Sonnet 5.5 can usually be served by retrying on another Claude model. [Refusals and
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build-with-claude/fallback-credit
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On models that include the 1M token context window by default, such as Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, and Claude Opus 4.8, the `context-1m-20
On models that include the 1M token context window by default, such as Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Sonnet 5.5, and
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build-with-claude/extended-thinking
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* You use Claude 4.7 or a later model, such as Claude Opus 5.5, Claude Sonnet 5, or Claude Fable 5.1, where `type: "enabled"` returns a 400 error.
* You use Claude 4.7 or a later model, such as Claude Opus 5.5, Claude Sonnet 5, Claude Sonnet 5.5, or Claude Fable 5.1, where `type: "enabled"` returns a 400 error.
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build-with-claude/effort
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- claude-sonnet-5-5
| Level | Description
| -------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------
| `max` | Absolute maximum capability with no constraints on token spending. Available on Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Mythos Pre
| `xhigh` | Extended capability for long-horizon work. Available on Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opus 5, Claude Op
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build-with-claude/context-windows
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Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 5, Claude Son
Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 5.5, Claude S
Claude Opus 4.7 and later Opus models, Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, and Claude Mythos 5 don't receive these injected tags. On these models, you can give the
Claude Opus 4.7 and later Opus models, Claude Sonnet 5.5, Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, and Claude Mythos 5 don't receive these injected tags. On these model
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build-with-claude/context-editing
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On Claude Fable 5.1 and Claude Opus 5.5, server-side context management never invalidates thinking blocks. Client-side edits to earlier turns can invalidate the thinking blocks in
On Claude Fable 5.1, Claude Opus 5.5, and Claude Sonnet 5.5, server-side context management never invalidates thinking blocks. Client-side edits to earlier turns can invalidate the
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build-with-claude/compaction-threshold
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- claude-sonnet-5-5
On Claude Fable 5.1, Claude Mythos 5.1, and Claude Opus 5.5, thinking blocks from before a `compaction` block aren't carried forward, so the summary is all the model has of that ea
On Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, and Claude Sonnet 5.5, thinking blocks from before a `compaction` block aren't carried forward, so the summary is all the m
On Claude Fable 5.1 and Claude Opus 5.5, remove the `thinking` and `redacted_thinking` blocks from any assistant turn you re-insert after the compaction block, or send `thinking.bl
On Claude Fable 5.1, Claude Opus 5.5, and Claude Sonnet 5.5, remove the `thinking` and `redacted_thinking` blocks from any assistant turn you re-insert after the compaction block,
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build-with-claude/compaction-thinking-blocks
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build-with-claude/compaction-thinking-blocks
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build-with-claude/claude-platform-on-aws
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build-with-claude/claude-platform-on-aws
| Claude Sonnet 5.5 | `claude-sonnet-5-5` |
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build-with-claude/claude-on-vertex-ai
| Claude Sonnet 5.5 | `claude-sonnet-5-5` |
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 5, and Claude Sonnet 4.6 have a [1M-token context
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 5.5, Claude Sonnet 5, and Claude Sonnet 4.6 have
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build-with-claude/claude-on-amazon-bedrock-legacy
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5, Claude Opus 4.8, and Claude Opus 4.7 are reachable through `InvokeModel` on `bedrock-runtime`.
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Opus 4.8, and Claude Opus 4.7 are reachable through `InvokeModel` on
[Mid-conversation system messages](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) are available through the InvokeModel API for Claude Fabl
[Mid-conversation system messages](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) are available through the InvokeModel API for Claude Fabl
Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 5, and Claude Sonnet 4.6 have a [1M-token context
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build-with-claude/claude-in-microsoft-foundry
This guide shows you how to set up and make API calls to Claude in Microsoft Foundry using one of Anthropic's client SDKs or direct HTTP requests. When you access Claude in Microso
This guide shows you how to set up and make API calls to Claude in Microsoft Foundry using one of Anthropic's client SDKs or direct HTTP requests. When you access Claude in Microso
Claude Sonnet 5.5 supports only Global Standard deployments.
* **Region scope:** Select Global, or for models hosted on Azure, Data Zone. Selecting Data Zone creates a US Data Zone Standard deployment, which keeps inference within the Uni
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build-with-claude/claude-in-amazon-bedrock
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build-with-claude/claude-in-amazon-bedrock
| Claude Sonnet 5.5 | `anthropic.claude-sonnet-5-5` | [See Access](https://platform.claude.com/docs/en/build-with-
The global endpoint is available for Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Sonnet 5, and Claude Haiku 4.5. For
The global endpoint is available for Claude Fable 5.1, Claude Fable 5, Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Sonnet 5.5, Claude Sonnet 5, and Cla
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build-with-claude/batch-processing
| Claude Sonnet 5.5 | $1 / MTok | $5 / MTok |
The `output-300k-2026-03-24` beta header raises the `max_tokens` cap to 300,000 for batch requests using Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Op
The `output-300k-2026-03-24` beta header raises the `max_tokens` cap to 300,000 for batch requests using Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Opus 4.7, Claude Op
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api/service-tiers
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api/service-tiers
Priority Tier is supported on all available Claude models except Claude Fable 5.1, Claude Mythos 5.1, Claude Mythos 5, [Claude Mythos Preview](https://anthropic.com/glasswing), Cla
Priority Tier is supported on all available Claude models except Claude Fable 5.1, Claude Mythos 5.1, Claude Mythos 5, [Claude Mythos Preview](https://anthropic.com/glasswing), Cla
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api/rate-limits
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api/rate-limits
| Claude Sonnet 5.5 | 1,000 | 2,
| Claude Sonnet 5.5 | 5,000 | 5,
| Claude Sonnet 5.5 | 10,000 | 10
*3 Sonnet 4.x rate limit is a total limit that applies to combined traffic across Sonnet 4.6 and Sonnet 4.5. Claude Sonnet 5 has a separate rate limit and is not part of this combi
*3 Sonnet 4.x rate limit is a total limit that applies to combined traffic across Sonnet 4.6 and Sonnet 4.5. Claude Sonnet 5.5 and Claude Sonnet 5 each have a separate rate limit a
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api/errors
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api/errors
On Claude Sonnet 5.5, thinking can't be set to `disabled`. Use `thinking: {"type": "between_tools"}` for the lowest thinking setting, which turns off up-front thinking. Sending `th
```text wrap
"thinking.type.disabled" is not supported for this model. Use "thinking.type.between_tools" for the lowest thinking setting, or "thinking.type.adaptive" and "output_config.effort"
```
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agents-and-tools/tool-use/tool-search-tool
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agents-and-tools/tool-use/tool-search-tool
| Claude Sonnet 5.5 (claude-sonnet-5-5) | `tool_search_tool_regex_20251119`, `tool_search_tool_bm25_20251119` |
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agents-and-tools/tool-use/programmatic-tool-calling
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agents-and-tools/tool-use/programmatic-tool-calling
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agents-and-tools/tool-use/parallel-tool-use
When `tool_choice` type is `any` or `tool`, setting `disable_parallel_tool_use: true` means Claude calls exactly one tool. Claude Opus 5.5, Claude Fable 5.1, and Claude Mythos 5.1
When `tool_choice` type is `any` or `tool`, setting `disable_parallel_tool_use: true` means Claude calls exactly one tool. Claude Opus 5.5, Claude Sonnet 5.5, Claude Fable 5.1, and
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agents-and-tools/tool-use/overview
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agents-and-tools/tool-use/overview
| Claude Sonnet 5.5 | 286 tokens
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agents-and-tools/tool-use/define-tools
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agents-and-tools/tool-use/define-tools
| Claude Opus 5.5, Claude Fable 5.1, and [Claude Mythos 5.1](https://anthropic.com/glasswing) | `any` and `tool` return a [400 error](https:
| Claude Opus 5.5, Claude Sonnet 5.5, Claude Fable 5.1, and [Claude Mythos 5.1](https://anthropic.com/glasswing) | `any` and `tool` return a [400 error](https:
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agents-and-tools/tool-use/computer-use-tool
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agents-and-tools/tool-use/computer-use-tool
- claude-sonnet-5-5
- On Amazon Bedrock, Claude Opus 5.5 accepts the earlier `computer_20251124` tool version as Claude Opus 5 does.
- On Amazon Bedrock, Claude Opus 5.5 and Claude Sonnet 5.5 accept the earlier `computer_20251124` tool version as Claude Opus 5 and Claude Sonnet 5 do.
* On Claude Fable 5.1 and Claude Opus 5.5, avoid pruning on the client: removing an earlier screenshot [invalidates every later thinking block](https://platform.claude.com/docs/en/
* On Claude Fable 5.1, Claude Opus 5.5, and Claude Sonnet 5.5, avoid pruning on the client: removing an earlier screenshot [invalidates every later thinking block](https://platform
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agents-and-tools/tool-use/browser-use-tool
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agents-and-tools/tool-use/advisor-tool
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agents-and-tools/tool-use/advisor-tool
Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, Claude Opus 5, Claude Fable 5, and Claude Mythos 5 advisors return the encrypted `advisor_redacted_result`. Every other advi
Claude Sonnet 5.5, Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, Claude Opus 5, Claude Fable 5, and Claude Mythos 5 advisors return the encrypted `advisor_redacted_result
To force a consult on a specific request instead of nudging, set `tool_choice` to `{"type": "tool", "name": "advisor"}`, subject to the constraints in [Forcing tool use](https://pl
To force a consult on a specific request instead of nudging, set `tool_choice` to `{"type": "tool", "name": "advisor"}`, subject to the constraints in [Forcing tool use](https://pl
| Executor models | Advisor models
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agents-and-tools/agent-skills/claude-api-skill
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agents-and-tools/agent-skills/claude-api-skill
* **Model migration:** Step-by-step guidance for migrating to newer Claude models (including the breaking changes and behavior shifts on [Claude Opus 5.5](https://platform.claude.c
* **Model migration:** Step-by-step guidance for migrating to newer Claude models (including the breaking changes and behavior shifts on [Claude Opus 5.5](https://platform.claude.c
* **Refusal fallback configuration**, adding `stop_reason: "refusal"` handling before reading response content and setting up a [fallback retry path](https://platform.claude.com/do
* **Refusal fallback configuration**, adding `stop_reason: "refusal"` handling before reading response content and setting up a [fallback retry path](https://platform.claude.com/do
For the full list of model-specific changes the skill applies, see [Migrating to Claude Opus 5.5 from Claude Opus 5](https://platform.claude.com/docs/en/models/opus-5-5/migration-g
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about-claude/pricing
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about-claude/pricing
| Claude Sonnet 5.5 | $2 / MTok | $2.50 / MTok |
| Claude Sonnet 5.5 | $1 / MTok | $5 / MTok |
| Claude Sonnet 5.5 | 286 tokens
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about-claude/models/choosing-a-model
| Speed and capability for everyday coding, agent, and enterprise workloads | Claude Sonnet 5 | Code generation, data analysis, content creation, visual understanding, ag
| Speed and capability for everyday coding, agent, and enterprise workloads | Claude Sonnet 5.5 | Code generation, data analysis, content creation, visual understanding, ag
<Card title="What's new in Claude Sonnet 5.5" icon="sparkle" href="https://platform.claude.com/docs/en/models/sonnet-5-5/whats-new-sonnet-5-5">
The latest Sonnet model: breaking changes, new features, and behavior differences
</Card>
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about-claude/model-deprecations
| claude-sonnet-5-5 | Active | N/A | Not sooner than September 28, 2027 |
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changelog
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changelog
<Update label="2.1.284" description="September 28, 2026">
* Added Claude Sonnet 5.5 (`claude-sonnet-5-5`), now the default Sonnet model on the Anthropic API — 1M context, $2/$10 per Mtok with \$0.20/Mtok cache reads
* Added a "Yes, but ask again next time" answer to auto mode's prompt before a read outside the working directories, so you can allow that one read and still be asked about later
* Added dollar amounts to the Claude apps gateway spend limit in `/usage` and the status line (for example "$271.40 / $500.00 spent this month") when the gateway runs this versio
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settings-reference
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settings-reference
| Key | Description
| :---------------------------------------------------------------------------------------------------- | :-------------------------------------------------------------------------
| [`advisorModel`](#advisormodel) | Pick which model answers when Claude asks the [advisor tool](/docs/en/advi
| [`agent`](#agent) | Start every session as a named [subagent](/docs/en/sub-agents) with its pr
| [`agentPushNotifEnabled`](#agentpushnotifenabled) | Let Claude send a [push notification to your phone](/docs/en/remote-contro
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model-config
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model-config
| Model alias | Behavior
| ---------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------
| **`default`** | Special value that clears any model override and reverts to the [runtime default for your account](#default-model-setting). Not itself a model alias
| **`best`** | Uses the model the [`fable` alias resolves to](#fable-alias-resolution) where Fable is available to you, otherwise the same model as `opus`
| **`fable`** | Uses the [Fable model for your provider](#fable-alias-resolution) for your hardest and longest-running tasks
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llm-gateway-protocol
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llm-gateway-protocol
| Format | Selected by | Endpoints
| :--------------------------------------- | :------------------------------------------------------------ | :----------------------------------------------------------------------
| Anthropic Messages | `ANTHROPIC_BASE_URL` | `/v1/messages`, `/v1/messages/count_tokens` (optional)
| Amazon Bedrock InvokeModel | `ANTHROPIC_BEDROCK_BASE_URL` with `CLAUDE_CODE_USE_BEDROCK=1` | `/model/{model}/invoke`, `/model/{model}/invoke-with-response-stream`,
| Google Cloud's Agent Platform rawPredict | `ANTHROPIC_VERTEX_BASE_URL` with `CLAUDE_CODE_USE_VERTEX=1` | `:rawPredict`, `:streamRawPredict`, `count-tokens:rawPredict` (optional
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interactive-mode
| Shortcut | Description
| :------------------------------------------------------------------------------------------- | :----------------------------------------------------------------------------------
| `Ctrl+C` | Interrupt, or clear input
| `Ctrl+X Ctrl+K` | Stop all running [background subagents](/docs/en/sub-agents#run-subagents-in-foregr
| `Ctrl+D` | Exit Claude Code session
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feature-availability
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feature-availability
| Feature | Pro | Max | Team | Enterprise |
| :-------------------------------------------------------------------------- | :-- | :-- | :------------ | :-------------------------------- |
| [Cloud sessions](/docs/en/claude-code-on-the-web) | ✓ | ✓ | ✓ | ✓ <sup><a href="#fn6">6</a></sup> |
| [Routines](/docs/en/routines) | ✓ | ✓ | ✓ | ✓ |
| [Remote Control](/docs/en/remote-control) | ✓ | ✓ | Admin-enabled | Admin-enabled |
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desktop
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desktop
| Mode | Settings key | Behavior
| ---------------------- | ------------------- | -----------------------------------------------------------------------------------------------------------------------------------
| **Manual** | `default` | Claude asks before editing files or running commands. You see a diff and can accept or reject each change.
| **Accept edits** | `acceptEdits` | Claude auto-accepts file edits and common filesystem commands like `mkdir`, `touch`, and `mv`, but still asks before running other
| **Plan** | `plan` | Claude reads files and runs commands to explore, then proposes a plan without editing your source code. Good for complex tasks wher
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costs
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costs
| Your role | What `/usage-credits` does
| :----------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------
| Pro or Max subscriber | Opens [**Settings > Usage**](https://claude.ai/settings/usage) on claude.ai in the browser. In its **Usage credits** section yo
| Team or Enterprise member with billing access | Opens your organization's usage settings, [**Admin settings > Usage**](https://claude.ai/admin-settings/usage), in the browser
| Team or Enterprise member without billing access | Asks you to confirm, then sends a request to your organization's admins. Before v2.1.211, Claude Code sent the request without
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context-window
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context-window
| Mechanism | After compaction
| :-------------------------------------------------------------------------------------------------------------------------------------------------------- | :---------------------
| System prompt and output style | Both still apply
| Project-root CLAUDE.md and unscoped rules | Re-injected from disk
| Auto memory | Re-injected from disk
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communications-kit
| Item | Why it matters
| ------------------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------
| `#claude-code` channel created and linked in the message | Gives questions one place to land
| Install command tested on at least one machine in your environment | Catches proxy or firewall issues before everyone hits them at once
| Security and data-handling link ready ([Data usage](/docs/en/data-usage) or your internal equivalent) | "Where does my code go?" will be the first reply
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advisor
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advisor
| Main model | Accepted advisors | Notes |
| ---------------------- | ------------------------------------------- | ---------------------------------------------------------------------------------------------- |
| Haiku 4.5 | Fable, Opus, Sonnet | Haiku can call the advisor but cannot act as one |
| Sonnet 4.6 | Fable, Opus, Sonnet | |
| Sonnet 5.5 or Sonnet 5 | Fable, Opus 4.7 or later, Sonnet 5 or later | A Sonnet 4.6 advisor is rejected, and the API refuses an Opus 4.6 advisor |
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settings-reference
On models that always think, such as Opus 5.5 and the Fable models, `false` has no effect. On [third-party providers](/docs/en/third-party-integrations) Claude Code omits the `thin
On models that always think, such as Opus 5.5, Sonnet 5.5, and the Fable models, `false` has no effect. On [third-party providers](/docs/en/third-party-integrations) Claude Code om
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prompt-caching
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prompt-caching
* **Effort level**: on most models, each effort level has its own cache, so changing effort mid-session recomputes the entire request. On Opus 5.5 and Fable 5.1 with an API key or
* **Effort level**: on most models, each effort level has its own cache, so changing effort mid-session recomputes the entire request. On Opus 5.5, Sonnet 5.5, and Fable 5.1 with a
[Automatic model fallback](/docs/en/model-config#automatic-model-fallback) on Fable models, Opus 5.5, and Opus 5 is also a model switch. When a safety classifier flags a request in
[Automatic model fallback](/docs/en/model-config#automatic-model-fallback) on Fable models, Opus 5.5, Sonnet 5.5, and Opus 5 is also a model switch. When a safety classifier flags
On Opus 5.5 and Fable 5.1 with an API key or a Claude subscription, changing effort keeps the cache, and Claude Code applies the new level without asking. This doesn't apply on Ama
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permission-modes
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permission-modes
* **Model**: on the Anthropic API and [Claude Platform on AWS](/docs/en/claude-platform-on-aws), Claude Opus 4.6 or later, Sonnet 4.6 or later, or a [Fable model](/docs/en/model-co
* **Model**: on the Anthropic API and [Claude Platform on AWS](/docs/en/claude-platform-on-aws), Claude Opus 4.6 or later, Sonnet 4.6 or later, or a [Fable model](/docs/en/model-co
Only Claude Sonnet 5, Opus 4.7 or later, and the Fable models are supported on these providers. On any other model, the session starts in Manual instead.
Only Claude Sonnet 5 or later, Opus 4.7 or later, and the Fable models are supported on these providers. On any other model, the session starts in Manual instead.
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model-config
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model-config
| Model alias | Behavior
| ---------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------
| **`default`** | Special value that clears any model override and reverts to the [runtime default for your account](#default-model-setting). Not itself a model alias
| **`best`** | Uses the model the [`fable` alias resolves to](#fable-alias-resolution) where Fable is available to you, otherwise the same model as `opus`
| **`fable`** | Uses the [Fable model for your provider](#fable-alias-resolution) for your hardest and longest-running tasks
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llm-gateway-protocol
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llm-gateway-protocol
* Same model as a built-in alias: when a discovered explicit ID names the model that a built-in alias currently resolves to, the picker shows only the alias row. For example, while
* Same model as a built-in alias: when a discovered explicit ID names the model that a built-in alias currently resolves to, the picker shows only the alias row. For example, while
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interactive-mode
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interactive-mode
| `Option+T` (macOS) or `Alt+T` (Windows/Linux) | Toggle extended thinking
| `Option+T` (macOS) or `Alt+T` (Windows/Linux) | Toggle extended thinking
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feature-availability
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feature-availability
<span id="fn2" style={{display: 'block', position: 'relative', top: '-120px'}} /><sup>2</sup> On these providers, auto mode supports only Claude Sonnet 5, Opus 4.7 or later, and th
<span id="fn2" style={{display: 'block', position: 'relative', top: '-120px'}} /><sup>2</sup> On these providers, auto mode supports only Claude Sonnet 5 or later, Opus 4.7 or late
* [Auto mode](/docs/en/auto-mode-config): Sonnet 5, Opus 4.7 or later, and Fable models only
* [Auto mode](/docs/en/auto-mode-config): Sonnet 5 or later, Opus 4.7 or later, and Fable models only
* [Auto mode](/docs/en/auto-mode-config): Sonnet 5, Opus 4.7 or later, and Fable models only
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errors
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errors
| `Opus 5.5's safeguards flagged this session`
| `<model>'s safeguards flagged this session`
* Run `claude update` and restart Claude Code. Opus 4.7 needs v2.1.111 or later. Opus 4.8 needs v2.1.154 or later. Sonnet 5 needs v2.1.197 or later. Opus 5 needs v2.1.219 or later.
* Run `claude update` and restart Claude Code. Opus 4.7 needs v2.1.111 or later. Opus 4.8 needs v2.1.154 or later. Sonnet 5 needs v2.1.197 or later. Opus 5 needs v2.1.219 or later.
* If you hit this in the [Agent SDK](/docs/en/agent-sdk/overview), upgrade the SDK package instead. Opus 4.8 needs TypeScript SDK v0.3.154 or later and Python SDK v0.2.88 or later.
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env-vars
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env-vars
| `CLAUDE_CODE_DISABLE_1M_CONTEXT` | Set to `1` to disable [1M context window](/docs/en/model-config#extended-context) support. When set, 1M model variants a
| `CLAUDE_CODE_DISABLE_ADAPTIVE_THINKING` | Set to `1` to disable [adaptive reasoning](/docs/en/model-config#adjust-effort-level) on Opus 4.6 and Sonnet 4.6 and fal
| `CLAUDE_CODE_DISABLE_1M_CONTEXT` | Set to `1` to disable [1M context window](/docs/en/model-config#extended-context) support. When set, 1M model variants a
| `CLAUDE_CODE_DISABLE_ADAPTIVE_THINKING` | Set to `1` to disable [adaptive reasoning](/docs/en/model-config#adjust-effort-level) on Opus 4.6 and Sonnet 4.6 and fal
| `CLAUDE_CODE_DISABLE_THINKING` | Set to `1` to omit the `thinking` parameter from API requests entirely. This is a compatibility option for proxies and g
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desktop
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desktop
[Extended thinking](/docs/en/model-config#extended-thinking) is enabled by default, which improves performance on complex reasoning tasks but uses additional tokens. On the Anthrop
On models with [adaptive reasoning](/docs/en/model-config#adjust-effort-level), `MAX_THINKING_TOKENS` values other than `0` are ignored because adaptive reasoning controls thinking
[Extended thinking](/docs/en/model-config#extended-thinking) is enabled by default, which improves performance on complex reasoning tasks but uses additional tokens. On the Anthrop
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costs
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costs
For simpler tasks where deep reasoning isn't needed, you can reduce costs by lowering the [effort level](/docs/en/model-config#adjust-effort-level) with `/effort` or in `/model`, o
For simpler tasks where deep reasoning isn't needed, you can reduce costs by lowering the [effort level](/docs/en/model-config#adjust-effort-level) with `/effort` or in `/model`, o
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context-window
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context-window
If you need a larger window rather than a smaller conversation, Fable models, Sonnet 5, Opus 4.6 and later, and Sonnet 4.6 support a 1 million token context window. See [Extended c
Sonnet 5 runs with the 1M context window and has no `[1m]` variant to select. See [Sonnet 5 context window](/docs/en/model-config#sonnet-5-context-window) for its auto-compaction t
If you need a larger window rather than a smaller conversation, Fable models, Sonnet 5 and later, Opus 4.6 and later, and Sonnet 4.6 support a 1 million token context window. See [
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communications-kit
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communications-kit
biology content falls back to Opus automatically. Opus 5.5 and Opus 5 run
their own checks too: flagged content switches to an earlier Opus, except
that flagged biology content on Opus 5 is refused.
biology content falls back to Opus automatically. Opus 5.5, Sonnet 5.5, and
Opus 5 run their own checks too: flagged content switches to an earlier model
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advisor
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advisor
| Main model | Accepted advisors | Notes |
| -------------------- | ---------------------------------- | ---------------------------------------------------------------------------------------------- |
| Haiku 4.5 | Fable, Opus, Sonnet | Haiku can call the advisor but cannot act as one |
| Sonnet 4.6 | Fable, Opus, Sonnet | |
| Sonnet 5 | Fable, Opus 4.7 or later, Sonnet 5 | A Sonnet 4.6 advisor is rejected, and the API refuses an Opus 4.6 advisor |
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claude-tag/concepts/settings-map
| Surface | Who changes it
| :--------------------------------------------------------------------------------------------- | :--------------------------------------------------------------------------------
| [Claude Tag admin page](https://claude.ai/admin-settings/claude-tag) | An Owner in your Claude organization
| [Usage page](https://claude.ai/admin-settings/usage/claude-tag) | An admin
| [Analytics page](https://claude.ai/analytics/claude-tag) | Anyone who can view the Analytics dashboard
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claude-tag/concepts/security-and-data
| Checkpoint | The guarantee
| :----------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------
| The sandbox | Holds no credentials
| Agent Proxy | Injects credentials from the credential store at request time, and blocks a request that no [connection](/docs/claude-tag/admins/add-connections#set-allowed-websit
| Your systems | See the agent's own accounts, so its actions there are attributable
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claude-tag/concepts/settings-map
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| [Claude Tag admin page](https://claude.ai/admin-settings/claude-tag) | An Owner in your Claude organization
| [Claude Tag admin page](https://claude.ai/admin-settings/claude-tag) | An Owner in your Claude organization
Everything an Owner configures for channels lives at [`claude.ai/admin-settings/claude-tag`](https://claude.ai/admin-settings/claude-tag). Settings there apply per scope (a channel
Everything an Owner configures for channels lives at [`claude.ai/admin-settings/claude-tag`](https://claude.ai/admin-settings/claude-tag). Most settings there apply per scope (a ch
* **Personal connectors**: on the Enterprise plan, whether Claude holds every result of a member's connector task for that member's review before posting it, and the topics an Owne
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claude-tag/concepts/security-and-data
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claude-tag/concepts/security-and-data
Claude uses a user's [personal connectors in a channel](/docs/claude-tag/concepts/personal-connectors) only for that user's own tasks, after the user allows it. The work runs with
Claude uses a user's [personal connectors in a channel](/docs/claude-tag/concepts/personal-connectors) only for that user's own tasks, after the user allows it. The work runs with
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* **Require human review of every message.** On the Enterprise plan, an admin can turn this switch on so that Claude holds every result for the requester's review, not only the one
* **Sensitive information requiring review.** Lists what the check looks for. An Owner can add topics of your own under **Additional topics**, for example "Board meeting notes are
* **Require human review of every message.** On the Enterprise plan, an admin can turn this switch on so that Claude holds every result for the requester's review, not only the one
* **Sensitive information requiring review.** Shows examples of what the check looks for. An Owner can add topics of their own under **Additional topics**, for example "Board meeti
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model-config
| Level | When to use it |
| :---------- | :------------------------------------------------------------------------------------------------------------------------------------- |
| `low` | Reserve for short, scoped, latency-sensitive tasks that are not intelligence-sensitive |
| `medium` | Reduces token usage for cost-sensitive work that can trade off some intelligence. The default on Opus 5.5 |
| `high` | Balances token usage and intelligence. The default on every model except Opus 5.5 and Opus 4.7 |
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cli-sdks-libraries/overview
title: CLI, SDKs, and libraries
title: SDKs, CLI, and libraries
description: "Official tools for building with the Claude API: the ant CLI, client SDKs in seven languages, and framework-specific libraries."
description: "Official tools for building with the Claude API: client SDKs in seven languages, the ant CLI, and framework-specific libraries."
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build-with-claude/thinking
Thinking removes that constraint. When thinking is active, Claude works through the problem in its own words before answering: it restates what is being asked, tries approaches, ch
Thinking removes that constraint. When thinking is active, Claude works through the problem in its own words before answering: it restates what is being asked, tries approaches, ch
, where they can also res
Web search is enabled for your organization unless an administrator has disabled it in the [Claude Console](https://platform.claude.com/settings/capabilities), where they can als
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Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5, Claude Fable 5, and Claude Mythos 5 advisors return the encrypted `advisor_redacted_result`. Every other advisor model in the
Claude Fable 5.1, Claude Mythos 5.1, Claude Opus 5.5, Claude Opus 5, Claude Fable 5, and Claude Mythos 5 advisors return the encrypted `advisor_redacted_result`. Every other advi
To force a consult on a specific request instead of nudging, set `tool_choice` to `{"type": "tool", "name": "advisor"}`, subject to the constraints in [Forcing tool use](https://pl
To force a consult on a specific request instead of nudging, set `tool_choice` to `{"type": "tool", "name": "advisor"}`, subject to the constraints in [Forcing tool use](https://pl
| Executor models | Advisor models
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connectors/github/index
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connectors/github/index
> Add files and folders from your GitHub repositories to a conversation or project so Claude can read your code
> Add a GitHub repository to a conversation, or files and folders from a repository to a project, so Claude can read your code
The GitHub integration lets you add files and folders from your GitHub repositories to a conversation or a project, so Claude can read your code and answer development questions wi
The GitHub integration lets you add a GitHub repository to a conversation, or files and folders from a repository to a project, so Claude can read your code and answer development
You can add repository content to a single conversation, or to a [project](https://support.claude.com/en/articles/9517075-what-are-projects), a workspace in Claude where a set of c
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| Argument | Description
| ----------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------
| `toolName` | The name of the tool Claude wants to use (for example, `"Bash"`, `"Write"`, `"Edit"`)
| `input` | The parameters Claude is passing to the tool. Contents vary by tool.
| Argument | Description |
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agent-sdk/typescript
| Parameter | Type | Description |
| :-------- | :--------------------------------------------------------------- | :---------------------------------------------------------------- |
| `prompt` | `string \| AsyncIterable<`[`SDKUserMessage`](#sdkusermessage)`>` | The input prompt as a string or async iterable for streaming mode |
| `options` | [`Options`](#options) | Optional configuration object (see Options type below) |
| Parameter | Type | Description |
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Nothing on this page matches that. Press Enter to search every page of the ledger.