1,120 pages for message.
Titles and paths first, then pages whose text carries it. Each row opens that page as this site last read it.
github
Claude Developer Platform · in the page
managed-agents/github
…json" \ -d '{ "events": [ { "type": "user.message", "content": [ { "type": "text", "text": "Fix the type error in src/util…
migration
Claude Developer Platform · in the page
managed-agents/migration
…ged-agents/migration description: Move an existing agent built on the Messages API or the Claude Agent SDK to Claude Managed Agents. featureMetadata: topic: title: Managed Agents url: https:…
multiagent-orchestration
Claude Developer Platform · in the page
managed-agents/multiagent-orchestration
…ys available until you archive it, so the agent can send it follow-up messages. With dynamic workflows, Claude writes a program to orchestrate agents without Claude's direct involvement. Context and r…
onboarding
Claude Developer Platform · in the page
managed-agents/onboarding
…r configuring your agent, you can start a test session directly, send messages, and watch the event stream without leaving the page. This is the fastest way to check that your system prompt and tool s…
overview
Claude Developer Platform · in the page
managed-agents/overview
…with Claude, each suited to different use cases: | | Messages API | Claude Managed Agents | | ------…
permission-policies
Claude Developer Platform · in the page
managed-agents/permission-policies
…} } ] ) ``` </CodeGroup> What you post in `user.message` events counts as your intent, and it can lead the server to allow a call it would otherwise deny. The server does not rea…
quickstart
Claude Developer Platform · in the page
managed-agents/quickstart
…generating outputs | | **Events** | Messages exchanged between your application and the agent (user turns, tool results, status updates) | #…
reference
Claude Developer Platform · in the page
managed-agents/reference
…------------------------------------------------------- | | `user.message` | A user message with text, image, or document content.…
scheduled-deployments
Claude Developer Platform · in the page
managed-agents/scheduled-deployments
…stead. * Deployments also require at least one initial event, a `user.message` or `user.define_outcome`, that starts each session's work. In a deployment file for `ant apply`, the text below the front…
secure-deployment
Claude Developer Platform · in the page
managed-agents/secure-deployment
…ry language. Keep keys out of system prompts, agent definitions, and messages. Do not give the agent a Claude API key or Claude API access token. Even when one is in a vault, code in the sandbox can…
self-hosted-sandboxes-memory
Claude Developer Platform · in the page
managed-agents/self-hosted-sandboxes-memory
…andboxes-operations#memory-stores-fail-to-mount) for the worker's log messages and their fixes.
session-observability
Claude Developer Platform · in the page
managed-agents/session-observability
…st, including thinking, tool calls with their inputs and results, and message text as it streams. You can filter the events and copy or download them as JSON. * **Inspector:** A resizable side panel w…
session-operations
Claude Developer Platform · in the page
managed-agents/session-operations
…----- | | `idle` | Agent is waiting for input, including user messages or tool confirmations. Sessions created without `initial_events` (java, php: `initialEvents`; csharp, go: `InitialEvents`…
session-threads
Claude Developer Platform · in the page
managed-agents/session-threads
…t start another turn until something else reaches it, such as a `user.message` or another thread's report. ## Archive a session thread Optionally archive a session thread when it has completed its w…
sessions
Claude Developer Platform · in the page
managed-agents/sessions
…end to the session at creation, processed in order. It supports `user.message` and [`user.define_outcome`](https://platform.claude.com/docs/en/managed-agents/define-outcomes) events, and accepts a max…
tools
Claude Developer Platform · in the page
managed-agents/tools
…ool-use/how-tool-use-works#user-defined-tools-client-executed) in the Messages API. You specify what operations are available and what they return, and Claude determines when and how to call them. Cl…
tools-web-restrictions
Claude Developer Platform · in the page
managed-agents/tools-web-restrictions
….BetaManagedAgentsAgentToolset20260401: configs := make([]json.RawMessage, len(toolset.Configs)) for i, config := range toolset.Configs { configs[i] = json.RawMessage(config.RawJSON())…
webhooks
Claude Developer Platform · in the page
managed-agents/webhooks
…awaiting input, for example, a tool permission approval or a new user message.…
workflow-runs
Claude Developer Platform · in the page
managed-agents/workflow-runs
…mes later. After an interrupt, that turn might not come: send a `user.message`, or read `result` (csharp, go: `Result`) yourself. After an archive or termination, it doesn't come.…
Or, for Claude Mythos 5.1, which offers the same capabilities to verified organizations:
Claude Developer Platform · in the page
models/fable-5-1/migration-guide
…and migration checklists. --- <Note> This guide covers migrating [Messages API](https://platform.claude.com/docs/en/build-with-claude/working-with-messages) code. If you use [Claude Managed Agents…
overview
Claude Developer Platform · in the page
models/fable-5-1/overview
…5-1#change-effort-mid-conversation-beta) (beta) * [Turn-scoped system messages](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1#turn-scoped-system-messages-beta) (beta) * [Rea…
whats-new-fable-5-1
Claude Developer Platform · in the page
models/fable-5-1/whats-new-fable-5-1
…5-1#change-effort-mid-conversation-beta) (beta) * [Turn-scoped system messages](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1#turn-scoped-system-messages-beta) (beta) * [Rea…
overview
Claude Developer Platform · in the page
models/fable-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/haiku-4-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
migration-guide
Claude Developer Platform · in the page
models/haiku-5-5/migration-guide
…t for each starting model. --- <Note> This guide covers migrating [Messages API](https://platform.claude.com/docs/en/build-with-claude/working-with-messages) code. If you use [Claude Managed Agents…
overview
Claude Developer Platform · in the page
models/haiku-5-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
whats-new-haiku-5-5
Claude Developer Platform · in the page
models/haiku-5-5/whats-new-haiku-5-5
…| | [Assistant message prefill returns an error](https://platform.claude.com/docs/en/models/haiku-5-5/migration-guide#replace-assistant-prefill)…
overview
Claude Developer Platform · in the page
models/mythos-5-1/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/mythos-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/opus-4-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/opus-4-6/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/opus-4-7/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/opus-4-8/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
migration-guide
Claude Developer Platform · in the page
models/opus-5-5/migration-guide
…t for each starting model. --- <Note> This guide covers migrating [Messages API](https://platform.claude.com/docs/en/build-with-claude/working-with-messages) code. If you use [Claude Managed Agents…
overview
Claude Developer Platform · in the page
models/opus-5-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
whats-new-opus-5-5
Claude Developer Platform · in the page
models/opus-5-5/whats-new-opus-5-5
…ptive"}`, which is equivalent. No beta header is involved. The error messages are: ```text wrap "thinking.type.disabled" is not supported for this model. Use "thinking.type.adaptive" and "output_con…
overview
Claude Developer Platform · in the page
models/opus-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
Models overview
Claude Developer Platform · in the page
models/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/sonnet-4-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
models/sonnet-4-6/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
migration-guide
Claude Developer Platform · in the page
models/sonnet-5-5/migration-guide
…very change by starting model. <Note> This guide covers migrating [Messages API](https://platform.claude.com/docs/en/build-with-claude/working-with-messages) code. If you use [Claude Managed Agents…
overview
Claude Developer Platform · in the page
models/sonnet-5-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
whats-new-sonnet-5-5
Claude Developer Platform · in the page
models/sonnet-5-5/whats-new-sonnet-5-5
…ng: {"type": "disabled"}` returns a 400 `invalid_request_error` whose message points to `between_tools`. `between_tools` is accepted at `low`, `medium`, and `high` effort. At `xhigh` or `max` effort,…
overview
Claude Developer Platform · in the page
models/sonnet-5/overview
…ens. 200k tokens is roughly 150k words. * **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5…
overview
Claude Developer Platform · in the page
release-notes/overview
…tings/capabilities) page of the Claude Console. With web fetch off, a Messages API request that includes the web fetch tool fails with a 400 error. In a Claude Managed Agents session, `web_fetch` call…
claude-fable-5
Claude Developer Platform · in the page
release-notes/system-prompts/claude-fable-5
…1'. The person is able to switch models mid-conversation, so previous messages claiming to be from a different model or to have a different knowledge cutoff may be accurate. Claude is accessible thro…
claude-fable-5-1
Claude Developer Platform · in the page
release-notes/system-prompts/claude-fable-5-1
…1'. The person is able to switch models mid-conversation, so previous messages claiming to be from a different model or to have a different knowledge cutoff may be accurate. Claude is accessible thro…
claude-haiku-3-5
Claude Developer Platform · in the page
release-notes/system-prompts/claude-haiku-3-5
…hat interface, mobile, desktop app, or via an API using the Anthropic messages API. The most up-to-date model is available with the model string "claude-3-5-sonnet-20241022". Claude can provide the in…
claude-haiku-4-5
Claude Developer Platform · in the page
release-notes/system-prompts/claude-haiku-4-5
…ic's site. The person can switch models mid-conversation, so earlier messages in this thread that identify as a different model or report a different knowledge cutoff may still be accurate. Claude i…
claude-haiku-5-5
Claude Developer Platform · in the page
release-notes/system-prompts/claude-haiku-5-5
…ic's site. The person can switch models mid-conversation, so earlier messages in this thread that identify as a different model or report a different knowledge cutoff may still be accurate. Claude i…