Model not found (not_found_error)

A requested model id is unavailable to this account or was retired.

83 issues · 4 open · 79 resolved (95%) · first seen Jun 24, 2025

First response · api

What to do now

Most likely: The API rejected or could not complete the request.

  1. Identify the HTTP status and error type before changing local configuration.
  2. Retry once with a short backoff; repeated failures should be compared with the official status page.
  3. If only one project fails, reproduce in a new short session to separate service trouble from request state.

These are conservative triage steps, not an official Anthropic fix. Use the issue and workaround evidence below before making a destructive configuration change.

Is this getting better or worse?

This class of problem is converging. 13 new reports in the last 90 days vs 31 in the 90 before — -58%. The open backlog peaked at 9 in 2026-03 and sits at 4 today.

0 2 5 7 9 2025-062025-112026-042026-08
2025-06 — First reports2026-03 — Peak backlog (9 open)2026-04 — Most new reports (15)

Derived by counting each matching issue from its creation date until it closed. First-party computation over the anthropics/claude-code tracker — the trend is not published anywhere upstream.

Which builds report this

41 of these reports name the Claude Code build they were running, spanning 29 releases. Heaviest reporters:

Report volume, not a defect count: an issue can mention a build without that build having caused the failure. Versions come from the version string in the bug-report template, matched against real published tags.

Do these get fixed?

Median time to close is 4 days across 79 closures. Of the 79 closures with a recorded reason, 22% were closed as completed and 62 as not-planned or duplicate. The most recent completed fix landed in 2026-08.

Workarounds reported by the community

8 of these issues post a workaround someone says worked. The highest-engagement ones:

[BUG] Task tool `model` parameter returns 404 - Blocks cost-optimized workflows (10-30x unnecessary spending)
…full model ID Actual: Test 3: Omit model parameter (current workaround) 5. Omit model parameter: Result: ✅ Works, but inherits Sonnet/Opus (defeats the purpose, 10-30x cost waste) --- Error Messages/Logs --- Technical An…
Found in the description of #18873 · resolved
[BUG] CLI 2.1.145 sends literal "claude-opus-4-7[1m]" as model name on session resume, hits 404, silently falls back to 200K
…d model name. Tested workaround that did NOT work Tried the workaround from < placed in . After restart, behavior unchanged — still shows and proxy logs confirm the same 404-then-fallback pattern. Possible I entered it i…
Found in the description of #60913 · resolved
[BUG] Agent model shorthand names (sonnet/opus/haiku) cause 404 errors - not translated like Task tool
…ting System macOS Terminal/Shell zsh Additional Information Workaround : Remove the field from agent definitions so they inherit from parent context, which does handle translation correctly. Related : This is similar to…
Found in the description of #17562 · resolved
Desktop app freezes during large builds — token stream stalls while timer continues
…ulti-file builds are initiated in the desktop app. The only workaround is to clear the conversation, which destroys all session context. Steps to Reproduce 1. Open Claude Code in the Claude Desktop app 2. Start a large b…
Found in the description of #51193 · resolved
[Bug] Skill frontmatter "model" field causes 404 API error
…25.3.0) - Available models: Opus 4.5, Sonnet 4.5, Haiku 4.5 Workaround Remove the field from skill frontmatter. The skill will inherit the model from the parent session. References - Documentation: (Frontmatter reference…
Found in the description of #32841 · resolved

Excerpts are quoted from the linked issue so you can judge relevance before opening it. Threads that only ask for a workaround, or report that there is none, are excluded. These are community suggestions, not official guidance from Anthropic — read the full thread before applying one.

Matching issues 1–83

Ranked by community engagement (reactions weighted over comments).

Related aggregations

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  2. API Error 500 (internal server error)

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  3. API Error 401 (authentication_error)

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  4. API Error 429 (rate_limit_error)

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  5. API Error 529 (overloaded_error)

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  6. API Error 403 (permission_error)

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