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
821pages tracked
774 changed this week · last read 23 Oct 2026
Claude Code CLI
228pages tracked
148 changed this week · last read 23 Oct 2026
Claude Documentation
280pages tracked
82 changed this week · last read 23 Oct 2026
Model Context Protocol
357pages tracked
171 changed this week · last read 23 Oct 2026
100 on this page
10,119 of the ledger's changes in api. Show every change
ReadSourcePageWhatLines
24 Sep 2026
83 pages
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api
agents-and-tools/tool-use/computer-use-tool
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agents-and-tools/tool-use/computer-use-tool
- On the Claude API and Google Cloud, Claude Opus 5.5 supports computer use only through the `computer_toolset_20260801` toolset and returns an error for the earlier `computer_
- On the Claude API and Google Cloud, Claude 5.5 and later models support computer use only through the `computer_toolset_20260801` toolset and return an error for the earlier
Upgrading from `computer_20251124` to the toolset is optional: the models listed for `computer_20251124` under [Earlier tool versions](https://platform.claude.com/docs/en/agents-an
Upgrading from `computer_20251124` to the toolset is optional: the models listed for `computer_20251124` under [Earlier tool versions](https://platform.claude.com/docs/en/agents-an
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agents-and-tools/tool-use/code-execution-tool
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agents-and-tools/tool-use/code-execution-tool
Code execution runs in server-side sandbox containers. Container data, including execution artifacts, uploaded files, and outputs, is retained for up to 30 days. This retention app
Code execution runs in server-side sandbox containers. Container data, including execution artifacts, uploaded files, and outputs, is retained for up to 30 days. This retention app
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agents-and-tools/tool-use/build-a-tool-using-agent
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agents-and-tools/tool-use/build-a-tool-using-agent
Rings 2 through 4 wrote the same loop by hand: call the API, check `stop_reason`, run tools, append results, repeat. The Tool Runner does this for you. Define each tool as a functi
Rings 2 through 4 wrote the same loop by hand: call the API, check `stop_reason`, run tools, append results, repeat. The Tool Runner does this for you. Define each tool as a functi
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agents-and-tools/mcp-connector
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agents-and-tools/mcp-connector
The conversion functions throw `UnsupportedMCPValueError` if an MCP value isn't supported by the Claude API (in Go, the helpers return an `UnsupportedValueError`; in Java and C#, t
The conversion functions fail with `UnsupportedMCPValueError` (go: `UnsupportedValueError`; java, csharp: `AnthropicInvalidDataException`) if an MCP value isn't supported by the Cl
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about-claude/models/optimizing-for-cost-and-intelligence
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about-claude/models/optimizing-for-cost-and-intelligence
* **Tradeoffs** exchange cost for intelligence: model choice, effort, output caps and task budgets, and multi-model architectures.
* **Tradeoffs** exchange cost for intelligence: model choice, effort, output caps and task budgets, an elapsed-time clock, and multi-model architectures.
| You want agent runs to finish sooner | Tell the model that time matters, and show it the elapsed time; on DRACO, HLE, and an internal physics set, runs took 33% to 69
These levers set where a single model sits between cost and intelligence: model choice, effort, re-running failures at a higher setting, and the budgets and caps it works within. S
These levers set where a single model sits between cost and intelligence: model choice, effort, re-running failures at a higher setting, the budgets and caps it works within, and w
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23 Sep 2026
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test-and-evaluate/strengthen-guardrails/handle-streaming-refusals
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test-and-evaluate/strengthen-guardrails/handle-streaming-refusals
# Stream request and check for refusal
# Check for refusal in the stream
if echo "$response" | grep -q '"stop_reason":"refusal"'; then
if echo "$response" | jq -R -e 'select(startswith("data: "))
| sub("^data: "; "") | fromjson
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managed-agents/webhooks
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managed-agents/webhooks
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI">
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI">
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managed-agents/migration
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managed-agents/migration
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI">
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managed-agents/agent-setup
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managed-agents/agent-setup
<CodeGroup>
<CodeGroup exclude="shell:CLI, python, typescript, csharp, go, java, php, ruby">
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manage-claude/workload-identity-federation
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manage-claude/workload-identity-federation
<CodeGroup>
<CodeGroup exclude="shell:CLI">
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manage-claude/spend-limits-api
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manage-claude/spend-limits-api
| `denied` | An admin declined. `spend_summary` is `null`. claude.ai hides that member's request button for 30 days from `resolved_at`; an admin can still raise the member's spen
| `denied` | An admin declined. `spend_summary` is `null`. The member can send a new request right away; only a `pending` request blocks a new one. An admin can still raise the m
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build-with-claude/thinking-tool-workflows
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build-with-claude/thinking-tool-workflows
```bash cURL
curl https://api.anthropic.com/v1/messages \
-H "anthropic-version: 2023-06-01" \
-H "content-type: application/json" \
-H "x-api-key: $ANTHROPIC_API_KEY" \
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build-with-claude/task-budgets
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build-with-claude/task-budgets
<CodeGroup>
<CodeGroup exclude="shell:cURL">
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build-with-claude/streaming
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build-with-claude/streaming
<CodeGroup>
<CodeGroup exclude="shell:cURL">
<CodeGroup>
<CodeGroup exclude="shell:cURL">
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build-with-claude/refusals-and-fallback
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build-with-claude/refusals-and-fallback
<Note>
**How refusals are billed:** You are not billed for a refusal that arrives before any output. `content` is empty, and token counts appear in `usage` but are not charged. The requ
</Note>
## How refusals are billed
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build-with-claude/prompt-caching
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build-with-claude/prompt-caching
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI, typescript, csharp, go, java, php, ruby">
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI, typescript, csharp, go, java, php, ruby">
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build-with-claude/mid-conversation-effort-example
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build-with-claude/mid-conversation-effort-example
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI">
<CodeGroup>
<CodeGroup exclude="shell:cURL, shell:CLI">
<CodeGroup>
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agents-and-tools/tool-use/tool-runner
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agents-and-tools/tool-use/tool-runner
The tool runner is in beta and available in the [Python SDK](https://github.com/anthropics/anthropic-sdk-python/blob/main/tools.md), [TypeScript SDK](https://github.com/anthropic
The tool runner is in beta and available in the [Python SDK](https://github.com/anthropics/anthropic-sdk-python/blob/main/tools.md), [TypeScript SDK](https://github.com/anthropic
Define each tool as a class implementing `Supplier<String>`. Annotate the class with `@JsonClassDescription` for the tool description, and each public field with `@JsonProperty
Define each tool as a `BetaRunnableTool` that pairs an input class with a function that runs when Claude calls the tool. Annotate the input class with `@JsonClassDescription` f
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about-claude/models/optimizing-for-cost-and-intelligence
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about-claude/models/optimizing-for-cost-and-intelligence
| Your situation | Do this
| ------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------
| Any workload, any model | Turn on prompt caching and trim unneeded tokens; both are free
| A person waits between turns | Use the 1-hour cache duration once about 1 turn in 20 follows a pause between 5 minutes and an hour and few gaps run over an ho
| Costs are too high; quality is fine | Sweep effort down on your current model
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release-notes/system-prompts/claude-opus-5-5
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release-notes/system-prompts/claude-opus-5-5
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release-notes/overview
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release-notes/overview
- [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) (research preview) is available for Claude Opus 5.5 on the Claude API.
* [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) (research preview) is available for Claude Opus 5.5 on the Claude API.
* We've launched **Claude Opus 5** (`claude-opus-5`), a step-change improvement over Claude Opus 4.8. Claude Opus 5 supports a [1M token context window](https://platform.claude.com
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models/sonnet-5/overview
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models/sonnet-5/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $2 / MTok |
| Output | $10 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $2.50 / MTok |
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models/sonnet-4-6/overview
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models/sonnet-4-6/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $3 / MTok |
| Output | $15 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $3.75 / MTok |
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models/sonnet-4-5/overview
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models/sonnet-4-5/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $3 / MTok |
| Output | $15 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $3.75 / MTok |
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models/overview
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models/overview
* **Reliable knowledge cutoff:** The date through which the model’s knowledge is most extensive and reliable. Training data cutoff (under Show all details) is the broader range of
* **Reliable knowledge cutoff:** The date through which the model’s knowledge is most extensive and reliable. Training data cutoff (under Additional details) is the broader range o
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models/opus-5/whats-new-opus-5
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models/opus-5/whats-new-opus-5
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models/opus-5/overview
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models/opus-5/overview
description: "Claude Opus 5 reference: lifecycle status, model IDs on every platform, context window, output limits, pricing, and migration resources. Claude Opus 5.5 is the curren
description: "Claude Opus 5 reference: lifecycle status, model IDs on every platform, context window, output limits, pricing, and migration resources. Claude Opus 5 is a legacy mod
For complex agentic coding and enterprise work
Although Claude Opus 5 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mode
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models/opus-5/migration-guide
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models/opus-5-5/whats-new-opus-5-5
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models/opus-5-5/whats-new-opus-5-5
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models/opus-5-5/overview
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models/opus-5-5/overview
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models/opus-5-5/migration-guide
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models/opus-5-5/migration-guide
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models/opus-4-8/overview
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models/opus-4-8/overview
Although Claude Opus 4.8 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
Although Claude Opus 4.8 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $5 / MTok |
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models/opus-4-7/overview
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models/opus-4-7/overview
Although Claude Opus 4.7 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
Although Claude Opus 4.7 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $5 / MTok |
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models/opus-4-6/overview
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models/opus-4-6/overview
Although Claude Opus 4.6 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
Although Claude Opus 4.6 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $5 / MTok |
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models/opus-4-5/overview
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models/opus-4-5/overview
Although Claude Opus 4.5 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
Although Claude Opus 4.5 is still available, you should consider migrating to Claude Opus 5.5 for improved performance. [See Claude Opus 5.5](https://platform.claude.com/docs/en/mo
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $5 / MTok |
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models/mythos-5/overview
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models/mythos-5/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $10 / MTok |
| Output | $50 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $12.50 / MTok |
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models/mythos-5-1/overview
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models/mythos-5-1/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $10 / MTok |
| Output | $50 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $12.50 / MTok |
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models/haiku-4-5/overview
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models/haiku-4-5/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $1 / MTok |
| Output | $5 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $1.25 / MTok |
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models/fable-5/overview
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models/fable-5/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $10 / MTok |
| Output | $50 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $12.50 / MTok |
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models/fable-5/migration-guide
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models/fable-5/migration-guide
If your code is on Claude Opus 4.7 or earlier, first apply the relevant [Migrating to Claude Opus 5](https://platform.claude.com/docs/en/models/opus-5/migration-guide) from-secti
If your code is on Claude Opus 4.7 or earlier, first apply the relevant [Migrating to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide) from-s
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models/fable-5-1/overview
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models/fable-5-1/overview
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------ |
| Input | $10 / MTok |
| Output | $50 / MTok |
| [5m cache write](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) | $12.50 / MTok |
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models/fable-5-1/migration-guide
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models/fable-5-1/migration-guide
<MultiFileExample language="cli" label="CLI">
```bash CLI
ant messages create < request.yaml
```
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managed-agents/files
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managed-agents/files
<MultiFileExample language="cli" label="CLI">
```bash CLI
ant beta:sessions create \
--agent agent_01J8XkN5uT3vHpLqRfWdY2 \
--environment-id env_01K2mPsT7hNwR4jXuLvCqD8 < session.yaml
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manage-claude/compliance-sessions
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manage-claude/compliance-sessions
Claude Science calls connectors (MCP servers) from code that it runs through its `repl` tool, not as separately named tools, so no block in a Claude Science transcript is named aft
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manage-claude/compliance-content-data
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manage-claude/compliance-content-data
The chat list endpoint defaults to organization-wide scope: leave off `user_ids[]` to include every chat under your parent organization. Add `order_by=updated_at` to sort by last u
The chat list endpoint defaults to organization-wide scope: leave off `user_ids[]` to include every chat under your parent organization. Add `order_by=updated_at` to sort by last u
That forward walk is also how you keep an export current across runs: persist the final page's `last_id` and resume from it as `after_id` on the next run. Because the list is order
That forward walk is also how you keep an export current across runs: persist the final page's `last_id` and resume from it as `after_id` on the next run. Because the list is order
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claude_api_primer
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claude_api_primer
* Claude Opus 5.5 (`claude-opus-5-5`, adaptive thinking only, always on)
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build-with-claude/working-with-messages
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build-with-claude/working-with-messages
The `temperature`, `top_p`, and `top_k` sampling parameters are not supported on Claude 4.7 and later models and Claude Mythos Preview. Setting them to a non-default value return
The `temperature`, `top_p`, and `top_k` sampling parameters are not supported on Claude 4.7 and later models and Claude Mythos Preview. Setting them to a non-default value return
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build-with-claude/thinking-steering-and-cost
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build-with-claude/thinking-steering-and-cost
| Effort level | Thinking behavior |
| ---------------- | ------------------------------------------------------------------------------------------------ |
| `max` | Claude thinks the most readily and at the greatest depth, with no constraint on thinking length. |
| `xhigh` | Claude thinks more readily and at greater depth than at `high`, suited to extended exploration. |
| `high` (default) | Claude thinks on most requests that benefit from it. Provides deep reasoning on complex tasks. |
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build-with-claude/refusals-and-fallback
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build-with-claude/refusals-and-fallback
* Thinking blocks from Claude Fable 5.1 or Claude Fable 5 pass through unchanged. Each retry re-sends your original request body, and the only blocks the middleware removes from co
* Thinking blocks from Claude Fable 5.1, Claude Opus 5.5, or Claude Fable 5 pass through unchanged. Each retry re-sends your original request body, and the only blocks the middlewa
* **Not redeeming a credit:** you can leave the earlier `thinking` and `redacted_thinking` blocks in place or strip them to save input tokens. The fallback model cannot use the
* **Not redeeming a credit:** you can leave the earlier `thinking` and `redacted_thinking` blocks in place or strip them to save input tokens. The fallback model normally can't
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build-with-claude/prompt-engineering/prompting-claude-opus-5-5
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build-with-claude/prompt-engineering/prompting-claude-opus-5
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build-with-claude/prompt-engineering/prompting-claude-opus-5
This guide covers the prompting patterns specific to Claude Opus 5. For the model's capabilities and API changes, see [What's new in Claude Opus 5](https://platform.claude.com/docs
This guide covers the prompting patterns specific to Claude Opus 5. For the model's specifications, see [Claude Opus 5](https://platform.claude.com/docs/en/models/opus-5/overview).
<Note>
For API changes when migrating from Claude Opus 4.8 (thinking on by default, and disabling thinking capped at `high` effort), see the [migration guide](https://platform.claude.co
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build-with-claude/prompt-engineering/prompting-claude-opus-4-8
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build-with-claude/prompt-engineering/prompting-claude-opus-4-8
This guide covers the prompting patterns specific to Claude Opus 4.8. For the API changes involved in moving from Claude Opus 4.8 to the latest Opus model, see [Migrating to Claude
This guide covers the prompting patterns specific to Claude Opus 4.8. For the API changes involved in moving from Claude Opus 4.8 to Claude Opus 5.5, see [Migrating to Claude Opus
For the API parameter changes since Claude Opus 4.7 (sampling parameters, effort default, 1M context window default, mid-conversation system messages, and refusal stop details),
For the API parameter changes since Claude Opus 4.7 (1M context window default and mid-conversation system messages), see [Migrating to Claude Opus 5.5 from Claude Opus 4.7](http
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build-with-claude/prompt-engineering/prompting-claude-fable-5-1
±changed
+1−1
apichanged
build-with-claude/prompt-engineering/prompting-claude-fable-5-1
Claude Fable 5.1's writing is generally a step up from earlier Claude models, with fewer stock phrases and less unexplained jargon. In some cases, though, its prose is denser than
Claude Fable 5.1's writing has few stock phrases and little unexplained jargon. In some cases, though, its prose is denser than Claude Fable 5's: sentences run longer and there are
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api
build-with-claude/prompt-engineering/claude-prompting-best-practices
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build-with-claude/prompt-engineering/claude-prompting-best-practices
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
* **Ask Claude to self-check.** Append something like "Before you finish, verify your answer against \[test criteria]." This catches errors reliably, especially for coding and math
* **Ask Claude to self-check.** Append something like "Before you finish, verify your answer against \[test criteria]." This catches errors reliably, especially for coding and math
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api
build-with-claude/prompt-caching
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apichanged
build-with-claude/prompt-caching
| **Dropped thinking blocks** | ✓ | ✓ | ✘ | When the API drops a Claude Fable 5.1 or Claude Mythos 5.1 thinking
| **Dropped thinking blocks** | ✓ | ✓ | ✘ | When the API drops a Claude Fable 5.1, Claude Mythos 5.1, or Claude
echo $prewarm->stopReason->value, PHP_EOL; // "max_tokens"
echo $prewarm->stopReason, PHP_EOL; // "max_tokens"
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api
build-with-claude/mid-conversation-system-messages
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+39−45
apichanged
build-with-claude/mid-conversation-system-messages
<MultiFileExample language="cli" label="CLI">
```bash CLI
ant beta:messages create --beta inline-tools-2026-09-15 < request.yaml
```
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api
build-with-claude/handling-stop-reasons
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apichanged
build-with-claude/handling-stop-reasons
RESPONSE=$(ant messages create --max-tokens 1024 --format jsonl < request.yaml)
RESPONSE=$(ant messages create --max-tokens 1024 --format jsonl <<'YAML'
model: claude-opus-5-5
tools:
- name: get_weather
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api
build-with-claude/fast-mode
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apichanged
build-with-claude/fast-mode
Fast mode is not available on Claude Opus 4.7. Requests to `claude-opus-4-7` with `speed: "fast"` return an error; unlike Claude Opus 4.6 (see the following note), requests do no
Fast mode is not available on Claude Opus 4.7. Requests to `claude-opus-4-7` with `speed: "fast"` return an error; unlike Claude Opus 4.6 (see the following note), requests do no
Fast mode is not available on Claude Opus 4.6. Requests to `claude-opus-4-6` with `speed: "fast"` do not return an error: they run at standard speed and are billed at [standard r
Fast mode is not available on Claude Opus 4.6. Requests to `claude-opus-4-6` with `speed: "fast"` do not return an error: they run at standard speed and are billed at [standard r
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api
build-with-claude/extended-thinking
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apichanged
build-with-claude/extended-thinking
* You are moving to Claude Opus 4.7, Claude Opus 4.8, Claude Opus 5, Claude Opus 5.5, Claude Sonnet 5, Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, or Claude Mythos 5, wher
* You use Claude 4.7 or a later model, such as Claude Opus 5.5, Claude Sonnet 5, or Claude Fable 5.1, where `type: "enabled"` returns a 400 error.
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api
build-with-claude/context-editing
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apichanged
build-with-claude/context-editing
cat > request.yaml <<'YAML'
ORIGINAL=$(ant beta:messages count-tokens \
--beta context-management-2025-06-27 \
--transform context_management.original_input_tokens \
--raw-output <<'YAML'
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Recorded here 23 Sep 2026 18:37 UTC
api
build-with-claude/compaction-threshold
±changed
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apichanged
build-with-claude/compaction-threshold
cat > request.yaml <<'YAML'
CURRENT=$(ant beta:messages count-tokens \
--beta compact-2026-01-12 \
--transform input_tokens \
--raw-output <<'YAML'
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api
build-with-claude/compaction-on-demand
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apichanged
build-with-claude/compaction-on-demand
<MultiFileExample language="cli" label="CLI">
```bash CLI
ant beta:messages create --beta compact-2026-09-04 < request.yaml
```
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api
build-with-claude/claude-on-vertex-ai
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apichanged
build-with-claude/claude-on-vertex-ai
| Claude Mythos 5.1 ([limited availability](https://anthropic.com/glasswing)) | `claude-mythos-5-1` |
| Claude Mythos 5 ([limited availability](https://anthropic.com/glasswing)) | `claude-mythos-5` |
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api
build-with-claude/claude-in-microsoft-foundry
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apichanged
build-with-claude/claude-in-microsoft-foundry
| Model | Default deployment name | Hosted on Azure | Hosted on Anthropic |
| :---------------- | :---------------------- | :-------------: | :-----------------: |
| Claude Fable 5.1 | `claude-fable-5-1` | | ✓ |
| Claude Fable 5 | `claude-fable-5` | | ✓ |
| Claude Opus 5.5 | `claude-opus-5-5` | ✓ | ✓ |
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api
build-with-claude/claude-in-amazon-bedrock
±changed
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apichanged
build-with-claude/claude-in-amazon-bedrock
| Model | Model ID | Access |
| --------------------- | ------------------------------- | --------------------------------------------------------------------------------------------------- |
| Claude Fable 5.1 | anthropic.claude-fable-5-1 | Open |
| Claude Fable 5 | anthropic.claude-fable-5 | Open |
| Claude Opus 5.5 | anthropic.claude-opus-5-5 | See [Access](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock#access) |
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api
build-with-claude/batch-processing
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apichanged
build-with-claude/batch-processing
* **MTok:** Million tokens. $5 / MTok is $5 for every million tokens.
* **Limited access:** Offered separately, by invitation only, as part of [Project Glasswing](https://anthropic.com/glasswing). For access, contact your Anthropic, AWS, or Google Cl
* **Retired:** May still be available on other cloud platforms. See [Model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations) for more.
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api
api/models/retrieve
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apichanged
api/models/retrieve
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/models/list
±changed
+5−1
apichanged
api/models/list
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/models
±changed
+10−2
apichanged
api/models
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+10 −2 lines
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api
api/messages/create
±changed
+10−2
apichanged
api/messages/create
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+10 −2 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/messages/count_tokens
±changed
+5−1
apichanged
api/messages/count_tokens
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/messages/batches/results
±changed
+5−1
apichanged
api/messages/batches/results
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/messages/batches/create
±changed
+5−1
apichanged
api/messages/batches/create
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/messages/batches
±changed
+25−5
apichanged
api/messages/batches
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+25 −5 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/messages
±changed
+46−10
apichanged
api/messages
- `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
- `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
- `"claude-opus-5-5"`
+46 −10 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/compliance/activities/list
±changed
+795−3
apichanged
api/compliance/activities/list
- `activity_types: optional array of "abuse_decision_received" or "account_deleted" or "admin_api_key_created" or 504 more`
- `activity_types: optional array of "abuse_decision_received" or "account_deleted" or "admin_api_key_created" or 507 more`
- `"gitlab_configuration_created"`
An organization admin created a self-managed GitLab configuration for syncing plugin marketplaces.
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api
api/compliance/activities
±changed
+7320−5760
apichanged
api/compliance/activities
No line of the body moved in this read.
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api
api/compliance
±changed
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apichanged
api/compliance
- `activity_types: optional array of "abuse_decision_received" or "account_deleted" or "admin_api_key_created" or 504 more`
- `activity_types: optional array of "abuse_decision_received" or "account_deleted" or "admin_api_key_created" or 507 more`
- `"gitlab_configuration_created"`
An organization admin created a self-managed GitLab configuration for syncing plugin marketplaces.
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Recorded here 23 Sep 2026 18:37 UTC
api
api/completions/create
±changed
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apichanged
api/completions/create
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+15 −3 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/completions
±changed
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apichanged
api/completions
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+20 −4 lines
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api
api/claude-code/routines-fire
±changed
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apichanged
api/claude-code/routines-fire
This is an experimental API. Request and response shapes, rate limits, and token semantics might change. Breaking changes ship behind new dated beta header versions, and the two
This is an experimental API. Request and response shapes, rate limits, and token semantics might change.
| Stability | Experimental; requires `anthropic-beta: experimental-cc-routine-2026-04-01` | Stable or standard
| Stability | Experimental | Stable or standard
Every request must include the `anthropic-beta: experimental-cc-routine-2026-04-01` header. Requests without it return `400 invalid_request_error`.
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api
api/beta/vaults/update
±changed
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apichanged
api/beta/vaults/update
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/retrieve
±changed
+5−1
apichanged
api/beta/vaults/retrieve
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/vaults/list
±changed
+5−1
apichanged
api/beta/vaults/list
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/delete
±changed
+5−1
apichanged
api/beta/vaults/delete
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
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api
api/beta/vaults/credentials/update
±changed
+5−1
apichanged
api/beta/vaults/credentials/update
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/credentials/retrieve
±changed
+5−1
apichanged
api/beta/vaults/credentials/retrieve
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/credentials/mcp_oauth_validate
±changed
+5−1
apichanged
api/beta/vaults/credentials/mcp_oauth_validate
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/credentials/list
±changed
+5−1
apichanged
api/beta/vaults/credentials/list
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/vaults/credentials/delete
±changed
+5−1
apichanged
api/beta/vaults/credentials/delete
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/vaults/credentials/create
±changed
+5−1
apichanged
api/beta/vaults/credentials/create
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/vaults/credentials/archive
±changed
+5−1
apichanged
api/beta/vaults/credentials/archive
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
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api
api/beta/vaults/credentials
±changed
+35−7
apichanged
api/beta/vaults/credentials
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+35 −7 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/vaults/create
±changed
+5−1
apichanged
api/beta/vaults/create
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
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api
api/beta/vaults/archive
±changed
+5−1
apichanged
api/beta/vaults/archive
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/vaults
±changed
+65−13
apichanged
api/beta/vaults
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+65 −13 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/user_profiles/update
±changed
+5−1
apichanged
api/beta/user_profiles/update
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/user_profiles/retrieve
±changed
+5−1
apichanged
api/beta/user_profiles/retrieve
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
api
api/beta/user_profiles/list
±changed
+5−1
apichanged
api/beta/user_profiles/list
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
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api
api/beta/user_profiles/create_enrollment_url
±changed
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apichanged
api/beta/user_profiles/create_enrollment_url
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 43 more`
- `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
- `"inline-tools-2026-09-15"`
- `"mcp-client-2026-09-15"`
+5 −1 lines
Recorded here 23 Sep 2026 18:37 UTC
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