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managed-agents/session-threads Changed · +6 / -8 lines

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5757 ```
5858 
5959 ```csharp C#
60 await foreach (var thread in (await client.Beta.Sessions.Threads.List(session.ID)).Paginate())
60 await foreach (var sessionThread in (await client.Beta.Sessions.Threads.List(session.ID)).Paginate())
6161 {
62 var label = thread.Agent.TryPickBetaManagedAgentsSessionThread(out var agent)
63 ? agent.Name
64 : thread.Agent.Json.GetProperty("type").GetString();
65 Console.WriteLine($"[{label}] {thread.Status.Raw()}");
62 var label = sessionThread.Agent.Name ?? sessionThread.Agent.Json.GetProperty("type").GetString();
63 Console.WriteLine($"[{label}] {sessionThread.Status.Raw()}");
6664 }
6765 ```
6866 
from line 484
486484 {
487485 foreach (var block in message.Content)
488486 {
489 if (block.Type == "text")
487 if (block.Value is BetaManagedAgentsTextBlock textBlock)
490488 {
491 Console.Write(block.Text);
489 Console.Write(textBlock.Text);
492490 }
493491 }
494492 }
from line 617
619617 var page = await client.Beta.Sessions.Threads.Events.List(thread.ID, new() { SessionID = session.ID });
620618 await foreach (var evt in page.Paginate())
621619 {
622 Console.WriteLine($"[{evt.Type}] {evt.ProcessedAt}");
620 Console.WriteLine($"[{evt.Json.GetProperty("type").GetString()}] {evt.ProcessedAt}");
623621 }
624622 ```
625623 

models/fable-5-1/migration-guide Changed · +3 / -2 lines

from line 1574
15741574 
15751575## Migrating to Claude Fable 5.1 from Claude Opus 4.8 or earlier
15761576 
1577First apply [Migrating to Claude Mythos 5 and Claude Fable 5 from Claude Opus 4.8](https://platform.claude.com/docs/en/models/fable-5/migration-guide#migrating-from-claude-opus-48) for the API-level changes from Claude Opus 4.8. It covers adaptive thinking, thinking output, refusals, effort, the caching minimum, pricing, and data retention. Then apply the remaining delta in [Migrating to Claude Fable 5.1 from Claude Fable 5](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-fable-5-to-claude-fable-5-1). On Claude Opus 4.7 or earlier, start with the matching [Claude Opus 5.5 migration guide](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide) section.
1577Work through the checklist below. On Claude Opus 4.7 or earlier, start with the matching [Claude Opus 5.5 migration guide](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide) section.
15781578 
15791579### Update your model name
15801580 
from line 1591
15911591* If your organization has a zero data retention (ZDR) arrangement, confirm eligibility first: these models aren't available under ZDR unless expressly authorized by Anthropic. Claude Opus 4.8 is available under ZDR.
15921592* Update the model name from `claude-opus-4-8` to `claude-fable-5-1` (or `claude-mythos-5-1`).
15931593* Remove any `thinking: {type: "disabled"}` configuration and revisit `max_tokens`. Requests without a `thinking` field run with adaptive thinking.
1594* Update response parsing that reads content by position, such as `content[0].text`: a response can now start with `thinking` blocks, so select content blocks by `type` instead.
15941595* Replace forced `tool_choice` (`any` or `tool`) with `auto` plus an explicit instruction (`user` turn or mid-conversation system message) and `strict: true` tools, or with JSON outputs.
15951596* Pass `thinking` blocks back unchanged and treat their text as display-only. Claude Fable 5.1 reads Claude Opus 4.8's thinking blocks: a conversation that moves onto `claude-fable-5-1` keeps its earlier reasoning. Claude Opus 4.8 can't read Claude Fable 5.1's blocks.
15961597* If your code builds the `messages` array itself, check whether it [edits earlier turns](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#fable-5-1-preserved-thinking). Integrations written for Claude Opus 4.8 and earlier often truncate old turns, strip or rebuild earlier messages, or refresh the `system` prompt each request, and Claude Opus 4.8 never objected. On `claude-fable-5-1` each of those invalidates later thinking blocks.
15971598* Handle `stop_reason: "refusal"`, read `stop_details.category`, and consider `fallbacks: "default"` (beta).
15981599* Apply the preserved-thinking, history-editing, behavior, per-message effort, and progress-update items from the [Claude Fable 5 checklist](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migration-checklist-fable-5-1-from-fable-5).
1599* Re-evaluate `effort` (start at `high`), review prompts near the 512-token caching minimum, and re-baseline cost and latency. Per-token pricing differs.
1600* Re-evaluate `effort` (start at `high`), review prompts near the 512-token [caching minimum](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#cache-limitations) (1,024 tokens on Claude Opus 4.8), and re-baseline cost and latency. Per-token pricing differs, and thinking tokens are billed as output tokens, so workloads that ran without thinking on Claude Opus 4.8 can produce more output tokens per request.
16001601 
16011602## Migrating to Claude Mythos 5.1 from Claude Mythos 5
16021603 

models/fable-5/introducing-claude-fable-5-and-claude-mythos-5 Page removed · 129 lines, page removed

## Models ## Refusals, fallback, and billing on Claude Fable 5 ### Refusals ### Fallback ### Billing ## Availability ## Prompting ## Messages API on Claude Fable 5 and Claude Mythos 5 ### Adaptive thinking is always on ### Raw thinking content is never returned ## Supported features ## Migrating from earlier models ## Next steps

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models/fable-5/migration-guide Page removed · 701 lines, page removed

## Migrating to Claude Mythos 5 and Claude Fable 5 from Claude Mythos Preview ### Update your model name ### Features not available on Claude Mythos 5 and Claude Fable 5 ### Token counting and billing ### Migration checklist ## Migrating to Claude Mythos 5 and Claude Fable 5 from Claude Opus 5 ### Update your model name ### What changed ### Migration checklist ## Migrating to Claude Mythos 5 and Claude Fable 5 from Claude Opus 4.8 ### Update your model name ### What changed ### Migration checklist

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models/fable-5/overview Changed · +2 / -6 lines

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66 
77**Legacy.** Released June 9, 2026.
88 
9Although Claude Fable 5 is still available, you should consider migrating to Claude Fable 5.1 for improved performance. [See Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) · [Migrate to Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-fable-5-to-claude-fable-5-1)
9Although Claude Fable 5 is still available, you should consider migrating to Claude Fable 5.1. [See Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) · [Migrate to Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-fable-5-to-claude-fable-5-1)
1010 
1111Model ID: `claude-fable-5`
1212 
1313Context window: 1M tokens · Max output: 128K tokens · Input pricing: $10 / MTok · Output pricing: $50 / MTok
1414 
15[Announcement](https://www.anthropic.com/news/claude-fable-5-mythos-5) · [What’s new](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5)
15[Announcement](https://www.anthropic.com/news/claude-fable-5-mythos-5)
1616 
1717## Fable vs. Mythos
1818 
from line 90
9090 
9191 <Card title="Claude Fable 5.1" icon="arrow-right" href="https://platform.claude.com/docs/en/models/fable-5-1/overview">
9292 The current Fable model: overview, specs, and resources.
93 </Card>
94 
95 <Card title="Introducing Claude Fable 5 and Claude Mythos 5" icon="star" href="https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5">
96 Capabilities, API changes, and availability for Claude Fable 5.
9793 </Card>
9894 
9995 <Card title="Prompting Claude Fable 5" icon="lightbulb" href="https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-fable-5">

release-notes/overview Changed · +3 / -2 lines

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1919### October 8, 2026
2020 
2121* The [Compliance API](https://platform.claude.com/docs/en/manage-claude/compliance-api) chat endpoints now also return chats from the unified Claude experience, in beta for Claude Enterprise organizations, with your existing Compliance Access Key. See [Retrieve and delete chats, files, and projects](https://platform.claude.com/docs/en/manage-claude/compliance-content-data).
22* The Compliance API can now download Claude Docs documents as Word files, in beta. See [Retrieve files and artifacts](https://platform.claude.com/docs/en/manage-claude/compliance-content-data#retrieve-files-and-artifacts).
2223 
2324### October 7, 2026
2425 
from line 264
263264 
264265### June 9, 2026
265266 
266* We've launched **Claude Fable 5** (`claude-fable-5`), our most capable model open to all customers, alongside **Claude Mythos 5** (`claude-mythos-5`) for Project Glasswing participants. Both models support a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) by default, 128k max output tokens, and always-on [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking). See [Introducing Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5) for capabilities, API changes, and availability.
267* We've launched **Claude Fable 5** (`claude-fable-5`), our most capable model open to all customers, alongside **Claude Mythos 5** (`claude-mythos-5`) for Project Glasswing participants. Both models support a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) by default, 128k max output tokens, and always-on [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking). See [Claude Fable 5](https://platform.claude.com/docs/en/models/fable-5/overview) for specifications, pricing, and availability.
267268* Claude Fable 5 and Claude Mythos 5 use the tokenizer introduced with Claude Opus 4.7. Compared to models before Claude Opus 4.7, the same text produces roughly 30% more tokens. The exact increase depends on the content and workload shape. Use the [token counting API](https://platform.claude.com/docs/en/build-with-claude/token-counting#token-counts-on-claude-fable-5) with `model: "claude-fable-5"` to measure your prompts under the new tokenizer.
268269* Claude Fable 5 runs safety classifiers on requests and during response generation. When a classifier declines a request, the Messages API returns `stop_reason: "refusal"`. You are not billed for a request refused before any output is generated. An opt-in `fallbacks` parameter (in beta on the Claude API and Claude Platform on AWS; not supported on the Message Batches API) re-runs refused requests on another model, billed at the fallback model's rates. See [Handling stop reasons](https://platform.claude.com/docs/en/build-with-claude/handling-stop-reasons).
269270* The [`stop_details.category`](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback#refusal-response) field on refusal responses now includes `"reasoning_extraction"` on Claude Fable 5, returned when a request is blocked under Anthropic's Terms of Service restrictions on reverse engineering or duplicating model outputs. The existing `"cyber"` and `"bio"` categories are unchanged. No beta header is required.
270* On Claude Fable 5 and Claude Mythos 5, [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) is the only thinking mode: `thinking: {"type": "disabled"}` is not supported, and manual extended thinking budgets and assistant prefill are not supported (both return a 400 error). See [Migrating from Claude Mythos Preview to Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/migration-guide#migrating-from-claude-mythos-preview).
271* On Claude Fable 5 and Claude Mythos 5, [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) is the only thinking mode: `thinking: {"type": "disabled"}` is not supported, and manual extended thinking budgets and assistant prefill are not supported (both return a 400 error).
271272* On Claude Fable 5 and Claude Mythos 5, `thinking.display` defaults to `"omitted"`, the same as Claude Opus 4.8, Claude Opus 4.7, and Claude Mythos Preview; set `display: "summarized"` to receive readable thinking summaries. The raw chain of thought is never returned; pass thinking blocks back unchanged in multi-turn conversations on the same model. See [Thinking output on Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/build-with-claude/thinking#thinking-output-on-claude-fable-5-and-claude-mythos-5).
272273* Claude Fable 5 requires 30-day data retention and is not available under zero data retention. See [Model-specific data retention requirements](https://platform.claude.com/docs/en/manage-claude/api-and-data-retention#model-specific-data-retention-requirements).
273274* Claude Managed Agents now supports [scheduled deployments](https://platform.claude.com/docs/en/managed-agents/scheduled-deployments), letting you run sessions on a cron schedule without managing your own scheduler.

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348348| Claude Haiku 5.5 | `anthropic.claude-haiku-5-5` | [See Access](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock#access) |
349349| Claude Haiku 4.5 | `anthropic.claude-haiku-4-5` | Open |
350350 
351Use Claude Code 2.1.255 or later with Claude Fable 5.1 on Amazon Bedrock, and 2.1.280 or later with Claude Opus 5.5 and Claude Haiku 5.5; run `claude update` to upgrade.
351Use the latest version of Claude Code with Claude in Amazon Bedrock; run `claude update` to upgrade.
352352 
353353<Tip>
354354 Upgrading to a newer Claude model? In Claude Code, run `/claude-api migrate` to apply model ID swaps and breaking parameter changes across your codebase. The skill detects which cloud platform your code targets and adjusts model ID formats and feature changes for that platform. See [Migrating to a newer Claude model](https://platform.claude.com/docs/en/agents-and-tools/agent-skills/claude-api-skill#migrating-to-a-newer-claude-model).

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1111* **Migration considerations** last, for prompts moving from earlier generations.
1212 
1313<Tip>
14 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 [What's new in Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1). For Claude Fable 5 capabilities and API changes, see [Introducing Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5). For migration guidance, see the [Migration guide](https://platform.claude.com/docs/en/about-claude/models/migration-guide). For Claude Opus 5.5, see [What's new in Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/whats-new-opus-5-5). For Claude Sonnet 5.5, see [What's new in Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/whats-new-sonnet-5-5). For Claude Haiku 5.5, see [What's new in Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/whats-new-haiku-5-5).
14 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 [What's new in Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1). For migration guidance, see the [Migration guide](https://platform.claude.com/docs/en/about-claude/models/migration-guide). For Claude Opus 5.5, see [What's new in Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/whats-new-opus-5-5). For Claude Sonnet 5.5, see [What's new in Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/whats-new-sonnet-5-5). For Claude Haiku 5.5, see [What's new in Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/whats-new-haiku-5-5).
1515</Tip>
1616 
1717## Model-specific guidance

build-with-claude/prompt-engineering/prompting-claude-fable-5 Changed · +2 / -2 lines

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44description: Behavioral differences and prompting patterns for Claude Fable 5 and Claude Mythos 5, covering effort, instruction following, long runs, memory, and scaffolding changes.
55---
66 
7This guide covers the prompting and scaffolding patterns specific to Claude Fable 5 and Claude Mythos 5. For the model's capabilities, API changes, pricing, and availability, see [Introducing Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5). For techniques that apply across all current Claude models, see [Prompting best practices](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/claude-prompting-best-practices).
7This guide covers the prompting and scaffolding patterns specific to Claude Fable 5 and Claude Mythos 5. For the model's specifications, pricing, and availability, see [Claude Fable 5](https://platform.claude.com/docs/en/models/fable-5/overview). For techniques that apply across all current Claude models, see [Prompting best practices](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/claude-prompting-best-practices).
88 
99Claude Fable 5 takes on problems that were previously too complex, long-running, or ambiguous for prior models, and is particularly effective at end-to-end work that takes a person hours, days, or weeks to complete. The teams seeing the best outcomes apply Claude Fable 5 to their hardest unsolved problems; testing it only on simpler workloads tends to undersell its capability range. It also performs reliably on more straightforward tasks.
1010 
from line 11
1111Claude Fable 5 has several behavioral differences from Claude Opus 4.8 that may require prompt or scaffolding updates. Capability improvements at this level are also a good prompt to re-evaluate which instructions, tools, and guardrails are still needed. The patterns below cover the behaviors that most often require tuning.
1212 
1313<Note>
14 For API parameter changes specific to Claude Fable 5 and Claude Mythos 5 (adaptive thinking only, summarized-only thinking output, no extended thinking budgets, the `refusal` stop reason and fallback handling), see [Introducing Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5).
14 For how thinking works on Claude Fable 5 and Claude Mythos 5 (adaptive thinking only, summarized-only thinking output, no extended thinking budgets), see [Thinking](https://platform.claude.com/docs/en/build-with-claude/thinking#configuring-thinking). For the `refusal` stop reason and fallback handling, see [Refusals and fallback](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback).
1515 
1616 Claude Fable 5 runs safety classifiers that target offensive cybersecurity techniques (such as building exploits, malware, or attack tooling), biology and life sciences content (such as lab methods or molecular mechanisms), and extraction of the model's summarized thinking. Benign cybersecurity work and beneficial life sciences tasks may also trigger these safeguards. To re-route declined requests automatically, configure [server-side or client-side fallback](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback) to Claude Opus 4.8.
1717</Note>

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7979Claude Opus 5.5 runs safety classifiers, including for biology, cybersecurity, and reasoning extraction.
8080 
8181* **Biology:** The biology safeguards are the same as Claude Fable 5.1's and are new if you're coming from Claude Opus 5. Everyday health and educational questions are unaffected. If the biology classifier gets in the way of your organization's life sciences work, apply to the [Life Sciences Verification Program](https://www.anthropic.com/news/life-sciences-verification-program).
82* **Cybersecurity:** Finding vulnerabilities in source code is allowed. High-risk dual-use cybersecurity activities are not.
82* **Cybersecurity:** Finding vulnerabilities in source code is allowed. High-risk dual-use cybersecurity activities are not. If the cybersecurity classifier gets in the way of your organization's legitimate security work, apply to the [Cyber Verification Program](https://support.claude.com/en/articles/14604842).
8383* **Reasoning extraction:** Requests that push the model to reproduce its internal reasoning in the response text may be declined with the `reasoning_extraction` category. If your prompts ask the model to write out its reasoning in the response, remove those instructions, set `display: "summarized"`, and read the summarized reasoning from the thinking blocks instead; see [Prompts written for thinking disabled](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-opus-5-5#prompts-written-for-thinking-disabled). You can still ask for a short explanation of the answer or a summary of the actions taken; see [Keep reasoning in thinking blocks](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback#keep-reasoning-in-thinking-blocks).
8484 
8585A classifier decline arrives as a normal response with `stop_reason: "refusal"` and a `stop_details` object naming the category. You can have the request retried automatically on a fallback model, except for `reasoning_extraction` declines, which server-side fallback returns to you instead of retrying; see [Refusals and fallback](https://platform.claude.com/docs/en/models/opus-5-5/whats-new-opus-5-5#refusals-and-fallback).

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172172* `reasoning_extraction`: the request asks the model to reproduce its internal reasoning in the response text.
173173* `general_harms`: the request falls under another usage-policy area. Benign work can also trigger this category.
174174 
175If the `bio` classifier blocks your organization's life sciences work, you can apply to the [Life Sciences Verification Program](https://www.anthropic.com/news/life-sciences-verification-program).
175If the `cyber` classifier blocks your organization's legitimate security work, you can apply to the [Cyber Verification Program](https://support.claude.com/en/articles/14604842). If the `bio` classifier blocks your organization's life sciences work, you can apply to the [Life Sciences Verification Program](https://www.anthropic.com/news/life-sciences-verification-program).
176176 
177177If you turn on [server-side fallback](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback#server-side-fallback) (beta), it retries `cyber` and `frontier_llm` declines on Claude Sonnet 5. It doesn't retry `bio`, `reasoning_extraction`, or `general_harms` declines. See [Refusals, fallback, and billing](https://platform.claude.com/docs/en/models/sonnet-5-5/whats-new-sonnet-5-5#refusals-fallback-and-billing).
178178 

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170170 
171171## Retrieve files and artifacts
172172 
173Files and artifacts are downloaded by ID, not listed independently. The IDs come from the chat messages endpoint in [Retrieve chats and messages](https://platform.claude.com/docs/en/manage-claude/compliance-content-data#retrieve-chats-and-messages) (the `files`, `generated_files`, and `artifacts` arrays on each message) or, for project-level uploads, from the [project attachments endpoint](https://platform.claude.com/docs/en/manage-claude/compliance-content-data#retrieve-projects-and-attachments).
173Files and artifacts are downloaded by ID. Except for Claude Docs documents (see the end of this section), they aren't listed independently. The IDs come from the chat messages endpoint in [Retrieve chats and messages](https://platform.claude.com/docs/en/manage-claude/compliance-content-data#retrieve-chats-and-messages) (the `files`, `generated_files`, and `artifacts` arrays on each message) or, for project-level uploads, from the [project attachments endpoint](https://platform.claude.com/docs/en/manage-claude/compliance-content-data#retrieve-projects-and-attachments).
174174 
175175Pick the endpoint that matches your ID type and the data you need. The same file content endpoint serves both chat files and project files.
176176 
from line 207
207207In curl, the `--remote-header-name` (`-J`) option, which normally saves a download under the `Content-Disposition` file name, does not read the `filename*` form, so name the saved file yourself with `--output`. In a script, take the name from the file's `filename` field in the chat messages or [Get file metadata](https://platform.claude.com/docs/en/api/compliance/apps/chats/files/retrieve) response, or decode `filename*`. Either way, it is the name the user gave the upload, so treat it as untrusted before using it as an output path: keep only the base name, allow only characters that are safe on your filesystem, and refuse names that begin with `-` or `.`.
208208 
209209Unlike the file content endpoint, the artifact content endpoint returns a JSON object. Pass the `version_id` from one of the entries in an assistant message's `artifacts` array, not the artifact's stable `id`; each new version of an artifact has its own `version_id`. The response's `content` field holds exactly that version's text, and its `title` and `artifact_type` fields describe the artifact. [Get artifact metadata](https://platform.claude.com/docs/en/api/compliance/apps/artifacts/retrieve) computes `size_bytes` and `md5` over the UTF-8 encoding of that text, so compare them with the `content` value rather than the whole response body.
210 
211Claude Docs documents are listed separately, by [List code artifacts](https://platform.claude.com/docs/en/api/compliance/code/artifacts/list), with `artifact_type` set to `claude_docs`. A document's `versions` list is empty and its `published_version_id` is `null`. To download a document's current text, call `GET /v1/compliance/apps/code/artifacts/{artifact_id}/content?multi_file_format=zip`. It returns a ZIP archive with one Word (.docx) file for each tab that holds text. Comments, uploaded files, and edit history aren't included. Downloading Claude Docs through the Compliance API is in beta.
210212 
211213## Retrieve projects and attachments
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77**Legacy.** Released October 15, 2025.
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9Although Claude Haiku 4.5 is still available, you should consider migrating to Claude Haiku 5.5 for improved performance. [See Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/overview) · [Migrate to Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/migration-guide)
9Although Claude Haiku 4.5 is still available, you should consider migrating to Claude Haiku 5.5. [See Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/overview) · [Migrate to Claude Haiku 5.5](https://platform.claude.com/docs/en/models/haiku-5-5/migration-guide)
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1111Model ID: `claude-haiku-4-5-20251001`
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1313Context window: 1M tokens · Max output: 128K tokens · Input pricing: $10 / MTok · Output pricing: $50 / MTok
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15[Announcement](https://www.anthropic.com/news/claude-fable-5-mythos-5) · [What’s new](https://platform.claude.com/docs/en/models/fable-5/introducing-claude-fable-5-and-claude-mythos-5) · [Migration guide](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-mythos-5-to-claude-mythos-5-1)
15[Announcement](https://www.anthropic.com/news/claude-fable-5-mythos-5) · [Migration guide](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-mythos-5-to-claude-mythos-5-1)
1616 
1717Claude Mythos 5 is available only to organizations verified through Anthropic’s verification programs, such as the [Cyber Verification Program](https://support.claude.com/en/articles/14604842). It has the same specifications and pricing as Claude Fable 5. To request access, apply to the program that covers your use case. [See Claude Fable 5](https://platform.claude.com/docs/en/models/fable-5/overview) · [How refusals and fallback work](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback)
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77**Legacy.** Released November 24, 2025.
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9Although 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/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-45)
9Although Claude Opus 4.5 is still available, you should consider migrating to Claude Opus 5.5. [See Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-45)
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1111Model ID: `claude-opus-4-5-20251101`
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77**Legacy.** Released February 5, 2026.
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9Although 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/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-46)
9Although Claude Opus 4.6 is still available, you should consider migrating to Claude Opus 5.5. [See Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-46)
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1111Model ID: `claude-opus-4-6`
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77**Legacy.** Released April 16, 2026.
88 
9Although 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/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-47)
9Although Claude Opus 4.7 is still available, you should consider migrating to Claude Opus 5.5. [See Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-47)
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1111Model ID: `claude-opus-4-7`
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77**Legacy.** Released May 28, 2026.
88 
9Although 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/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-4-8)
9Although Claude Opus 4.8 is still available, you should consider migrating to Claude Opus 5.5. [See Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-4-8)
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1111Model ID: `claude-opus-4-8`
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77**Legacy.** Released July 24, 2026.
88 
9Although 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/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-5)
9Although Claude Opus 5 is still available, you should consider migrating to Claude Opus 5.5. [See Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/overview) · [Migrate to Claude Opus 5.5](https://platform.claude.com/docs/en/models/opus-5-5/migration-guide#migrating-from-claude-opus-5)
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1111Model ID: `claude-opus-5`
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77**Legacy.** Released February 17, 2026.
88 
9Although Claude Sonnet 4.6 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/en/models/sonnet-5-5/overview) · [Migrate to Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/migration-guide#migrating-from-claude-sonnet-4-6)
9Although Claude Sonnet 4.6 is still available, you should consider migrating to Claude Sonnet 5.5. [See Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/overview) · [Migrate to Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/migration-guide#migrating-from-claude-sonnet-4-6)
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1111Model ID: `claude-sonnet-4-6`
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77**Legacy.** Released June 30, 2026.
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9Although Claude Sonnet 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/en/models/sonnet-5-5/overview) · [Migrate to Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/migration-guide#migrating-from-claude-sonnet-5)
9Although Claude Sonnet 5 is still available, you should consider migrating to Claude Sonnet 5.5. [See Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/overview) · [Migrate to Claude Sonnet 5.5](https://platform.claude.com/docs/en/models/sonnet-5-5/migration-guide#migrating-from-claude-sonnet-5)
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1111Model ID: `claude-sonnet-5`
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