fabro/docs/superpowers
Bryan Helmkamp a4e8987da8
feat(llm): add Claude Fable 5 support (#482)
## Summary

Adds Anthropic Claude Fable 5 as a first-class Fabro model without
changing the default Anthropic model. The catalog now exposes
`claude-fable-5` with `fable` and `claude-fable` aliases, 1M context,
128k max output, effort levels, vision/tools, prompt caching, and the
documented pricing.

The Anthropic adapter now handles Fable's API behavior directly: it uses
the `claude-fable-5` API ID, omits the legacy 1M context beta header,
avoids injecting default `thinking`, preserves `output_config.effort`,
omits deprecated `temperature`/`top_p` sampling fields for Fable, and
rejects unsupported manual enabled/disabled thinking configs locally.

Fable refusals are converted into content-filter LLM errors with
`stop_details` preserved. Those refusal errors are fallback-eligible, so
existing `run.model.fallbacks` chains work for both prompt and agent
paths, while no-fallback refusals surface clearly as LLM errors.

## Live QA

Manually exercised the PR branch against a live Anthropic API key from
`~/.fabro.bak/.env.bak` using a temporary local harness that was removed
before commit. The run covered non-streaming completion via `fable`,
token counting via `claude-fable`, streaming completion, the deep
model-test path with tools/reasoning, local rejection of manual thinking
config, and a live refusal probe. The live run initially exposed
Anthropic's Fable rejection of `temperature`; this PR now strips
deprecated sampling fields for Fable and the live harness then passed
6/6 checks.

## Testing

- `cargo test -p fabro-llm --test live_fable_manual -- --nocapture
--test-threads=1` -> 6 passed against live Anthropic, temporary harness
removed afterward
- `cargo nextest run -p fabro-llm
encode_fable_uses_api_id_effort_and_omits_1m_beta`
- `cargo nextest run -p fabro-model -p fabro-llm -p fabro-workflow` ->
1808 passed, 41 skipped
- `cargo +nightly-2026-04-14 fmt --check --all`
- `cargo insta pending-snapshots` -> no pending snapshots
- `git diff --check`

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-06-10 14:01:56 -04:00
..
plans feat(llm): add Claude Fable 5 support (#482) 2026-06-10 14:01:56 -04:00
specs feat(fabro-web): port /chats/new + /chats/:id from prototype (#289) 2026-05-16 17:10:16 -04:00