Source Intelligence
Sweep 28 Aug 2026 · 00:00Z Build v2.1.250 478 read Stable v2.1.236 Latest v2.1.250 Next v2.1.251 Feeds RSS JSON llms.txt
Reading a new release v2.1.251 Analysing changes · 2/5 Writing the entries · 2/4 steps 470 findings $18.91 so far

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

Search the documentation

50 pages for claude-opus-4-5.

Titles and paths first, then pages whose text carries it. Each row opens that page as this site last read it. Cut at 50, so a narrower query shows the rest.

claude-opus-4-5 Claude Developer Platform · title release-notes/system-prompts/claude-opus-4-5 model-deprecations Claude Developer Platform · in the page about-claude/model-deprecations …e | N/A | Not sooner than February 5, 2027 | | claude-opus-4-5-20251101 | Active | N/A | Not sooner than November 24, 2026 | | claude-opus-4-1-20250805… Or, for the model with the same capabilities and no access approval requirement: Claude Developer Platform · in the page about-claude/models/migration-guide …d. ##### Update your model name ```python # Opus migration model = "claude-opus-4-5" # Before model = "claude-opus-5" # After ``` ##### Breaking changes 1. **Prefill removal** is covered in the… code-execution-tool Claude Developer Platform · in the page agents-and-tools/tool-use/code-execution-tool …e_execution_20260120`, `code_execution_20260521` | | Claude Opus 4.5 (claude-opus-4-5-20251101) | `code_execution_20250825`, `code_execution_20260120`, `code_execution_20260521` | | Claude Sonnet… Process results programmatically Claude Developer Platform · in the page agents-and-tools/tool-use/programmatic-tool-calling …| Claude Sonnet 4.6 (claude-sonnet-4-6) | | Claude Opus 4.5 (claude-opus-4-5-20251101) | | Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) | For the full code execution tool version matri… tool-search-tool Claude Developer Platform · in the page agents-and-tools/tool-use/tool-search-tool …egex_20251119`, `tool_search_tool_bm25_20251119` | | Claude Opus 4.5 (claude-opus-4-5-20251101) | `tool_search_tool_regex_20251119`, `tool_search_tool_bm25_20251119` | | Claude Sonnet 4.5 (claude-… Beta Claude Developer Platform · in the page api/beta …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-202… Agents Claude Developer Platform · in the page api/beta/agents …1"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Archive Agent Claude Developer Platform · in the page api/beta/agents/archive …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Create Agent Claude Developer Platform · in the page api/beta/agents/create …1"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… List Agents Claude Developer Platform · in the page api/beta/agents/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Get Agent Claude Developer Platform · in the page api/beta/agents/retrieve …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Update Agent Claude Developer Platform · in the page api/beta/agents/update …1"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Versions Claude Developer Platform · in the page api/beta/agents/versions …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… List Agent Versions Claude Developer Platform · in the page api/beta/agents/versions/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Messages Claude Developer Platform · in the page api/beta/messages …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-202… Batches Claude Developer Platform · in the page api/beta/messages/batches …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus… Create a Message Batch Claude Developer Platform · in the page api/beta/messages/batches/create …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus… Retrieve Message Batch results Claude Developer Platform · in the page api/beta/messages/batches/results …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus… Count tokens in a Message Claude Developer Platform · in the page api/beta/messages/count_tokens …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-202… Create a Message Claude Developer Platform · in the page api/beta/messages/create …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-202… Sessions Claude Developer Platform · in the page api/beta/sessions …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Archive Session Claude Developer Platform · in the page api/beta/sessions/archive …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Create Session Claude Developer Platform · in the page api/beta/sessions/create …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Events Claude Developer Platform · in the page api/beta/sessions/events …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… List Events Claude Developer Platform · in the page api/beta/sessions/events/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Stream Events Claude Developer Platform · in the page api/beta/sessions/events/stream …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… List Sessions Claude Developer Platform · in the page api/beta/sessions/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Get Session Claude Developer Platform · in the page api/beta/sessions/retrieve …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Threads Claude Developer Platform · in the page api/beta/sessions/threads …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Archive Session Thread Claude Developer Platform · in the page api/beta/sessions/threads/archive …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Events Claude Developer Platform · in the page api/beta/sessions/threads/events …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… List Session Thread Events Claude Developer Platform · in the page api/beta/sessions/threads/events/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Stream Session Thread Events Claude Developer Platform · in the page api/beta/sessions/threads/events/stream …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… List Session Threads Claude Developer Platform · in the page api/beta/sessions/threads/list …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Get Session Thread Claude Developer Platform · in the page api/beta/sessions/threads/retrieve …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Update Session Claude Developer Platform · in the page api/beta/sessions/update …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Completions Claude Developer Platform · in the page api/completions …51001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"` Power… Create a Text Completion Claude Developer Platform · in the page api/completions/create …51001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"` Power… Messages Claude Developer Platform · in the page api/messages …51001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"` Power… Batches Claude Developer Platform · in the page api/messages/batches …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Create a Message Batch Claude Developer Platform · in the page api/messages/batches/create …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"`… Retrieve Message Batch results Claude Developer Platform · in the page api/messages/batches/results …Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-2025110… Count tokens in a Message Claude Developer Platform · in the page api/messages/count_tokens …51001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"` Power… Create a Message Claude Developer Platform · in the page api/messages/create …51001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Powerful intelligence for long-running agents and coding - `"claude-opus-4-5-20251101"` Power… claude-in-microsoft-foundry Claude Developer Platform · in the page build-with-claude/claude-in-microsoft-foundry …| | ✓ | | Claude Opus 4.5 | claude-opus-4-5 | | ✓ | | Claude Sonnet 5 | claude-sonnet-5 | ✓… claude-on-amazon-bedrock-legacy Claude Developer Platform · in the page build-with-claude/claude-on-amazon-bedrock-legacy …| No | No | No | | Claude Opus 4.5 | anthropic.claude-opus-4-5-20251101-v1:0 | Yes | Yes | Yes | No | No | | Claude Opus 4.1 Deprecated. | anthropic.claude-opus-… claude-on-vertex-ai Claude Developer Platform · in the page build-with-claude/claude-on-vertex-ai …d. | claude-3-7-sonnet\@20250219 | | Claude Opus 4.5 | claude-opus-4-5\@20251101 | | Claude Opus 4.1 Deprecated. | claude-opus-4-1\@20250805 | | Claude Opus 4 Deprecated. | clau… claude-platform-on-aws Claude Developer Platform · in the page build-with-claude/claude-platform-on-aws …5 | | Claude Sonnet 4.6 | claude-sonnet-4-6 | | Claude Opus 4.5 | claude-opus-4-5 | | Claude Sonnet 4.5 | claude-sonnet-4-5 | | Claude Haiku 4.5 | claude-haiku-4-5 | Model IDs are identical t… effort Claude Developer Platform · in the page build-with-claude/effort …pus-4-7`, `claude-opus-4-6`, `claude-sonnet-5`, `claude-sonnet-4-6`, `claude-opus-4-5-20251101` - Platforms: Claude API, Claude Platform on AWS, Amazon Bedrock, Google Cloud, Microsoft Foundry The ef…