27 pages for claude-mythos-preview.
Titles and paths first, then pages whose text carries it. Each row opens that page as this site last read it.
model-deprecations
Claude Developer Platform · in the page
about-claude/model-deprecations
…| N/A | Not sooner than June 9, 2027 | | claude-mythos-preview | Deprecated | June 9, 2026 | To be announced | | claude-opus-5-5…
Or, for the model with the same capabilities and no access approval requirement:
Claude Developer Platform · in the page
about-claude/models/migration-guide
…model-deprecations). #### Update your model name ```python model = "claude-mythos-preview" # Before model = "claude-mythos-5" # After # Or, for the model with the same capabilities and no access…
Beta
Claude Developer Platform · in the page
api/beta
…ligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude…
Messages
Claude Developer Platform · in the page
api/beta/messages
…ligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude…
Batches
Claude Developer Platform · in the page
api/beta/messages/batches
…nce for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to cl…
Create a Message Batch
Claude Developer Platform · in the page
api/beta/messages/batches/create
…nce for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to cl…
Retrieve Message Batch results
Claude Developer Platform · in the page
api/beta/messages/batches/results
…nce for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to cl…
Count tokens in a Message
Claude Developer Platform · in the page
api/beta/messages/count_tokens
…ligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude…
Create a Message
Claude Developer Platform · in the page
api/beta/messages/create
…ligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude…
Completions
Claude Developer Platform · in the page
api/completions
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit htt…
Create a Text Completion
Claude Developer Platform · in the page
api/completions/create
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit htt…
Messages
Claude Developer Platform · in the page
api/messages
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit htt…
Batches
Claude Developer Platform · in the page
api/messages/batches
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit…
Create a Message Batch
Claude Developer Platform · in the page
api/messages/batches/create
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit…
Retrieve Message Batch results
Claude Developer Platform · in the page
api/messages/batches/results
…werful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. V…
Count tokens in a Message
Claude Developer Platform · in the page
api/messages/count_tokens
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit htt…
Create a Message
Claude Developer Platform · in the page
api/messages/create
…Powerful intelligence for long-running agents and coding - `"claude-mythos-preview"` **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit htt…
claude-in-amazon-bedrock
Claude Developer Platform · in the page
build-with-claude/claude-in-amazon-bedrock
…ilability](https://anthropic.com/glasswing)) | `anthropic.claude-mythos-preview` | Invitation only | | C…
sent_count = len(messages sent in the compaction request)
Claude Developer Platform · in the page
build-with-claude/compaction
…able-5-1`, `claude-mythos-5-1`, `claude-fable-5`, `claude-mythos-5`, `claude-mythos-preview`, `claude-opus-5`, `claude-opus-4-8`, `claude-opus-4-7`, `claude-opus-4-6`, `claude-sonnet-5`, `claude-sonne…
compaction-background
Claude Developer Platform · in the page
build-with-claude/compaction-background
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
compaction-keep-recent-turns
Claude Developer Platform · in the page
build-with-claude/compaction-keep-recent-turns
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
compaction-on-demand
Claude Developer Platform · in the page
build-with-claude/compaction-on-demand
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
compaction-thinking-blocks
Claude Developer Platform · in the page
build-with-claude/compaction-thinking-blocks
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
compaction-threshold
Claude Developer Platform · in the page
build-with-claude/compaction-threshold
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
effort
Claude Developer Platform · in the page
build-with-claude/effort
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
structured-outputs
Claude Developer Platform · in the page
build-with-claude/structured-outputs
…- claude-mythos-5-1 - claude-fable-5 - claude-mythos-5 - claude-mythos-preview - claude-opus-5-5 - claude-opus-5 - claude-opus-4-8 - claude-opus-4-7 - claude-opus-4-6…
overview
Claude Developer Platform · in the page
resources/overview
…thos Preview System Card" icon="file" href="https://www.anthropic.com/claude-mythos-preview-system-card"> Detailed documentation of Claude Mythos Preview. </Card> <Card title="Claude Sonnet 4…