Add Anthropic (Claude) API backend by bddap-bot · Pull Request #30 · bddap/refac

bddap-bot · 2026-05-29T17:45:01Z

Hooks refac into Anthropic via API key, as requested.

What changed

Default backend is Claude (Messages API, claude-opus-4-8). OpenAI still supported; default model gpt-5.5.
Provider selection: explicit provider (config or REFAC_PROVIDER) wins; unset → inferred from which API keys are configured (only OpenAI → OpenAI; Anthropic-only/both/neither → Anthropic). refac login [--provider anthropic|openai], else an interactive pick.
Provider-agnostic core Message: { role: Role, fields: Vec<String>, cache: bool }. A turn carries one or more text fields (a transform user turn is [selected, transform]); cache marks the last turn of a static prefix. Each backend adapts it:
- Anthropic (src/anthropic.rs): /v1/messages via reqwest; each field → a content block; empty fields render as (empty) (the API rejects empty text); cache → cache_control: ephemeral on the turn's last block (caches system + few-shot, so repeat calls only pay for the appended input); System → top-level system.
- OpenAI (src/main.rs): its own OpenAiMessage wire type; the adapter joins a turn's fields and drops cache.
Config: provider (optional), model (optional, defaulted per provider). Secrets hold either/both keys; honor ANTHROPIC_API_KEY / OPENAI_API_KEY.

Testing

cargo test — 5 passing (request-builder shape + cache placement, empty-field (empty) rendering, no-system, provider inference + override).
Live-tested against Anthropic: a normal transform (me like toast / correct grammar → I like toast.) and an empty-selected generate ("" / command to list files recursively → find .).

🤖 Generated with Claude Code

refac now defaults to the Claude Messages API (model claude-opus-4-8); OpenAI remains available via `provider = "openai"`. New `src/anthropic.rs` talks to the REST API with reqwest (no official Rust SDK): x-api-key + anthropic-version headers, top-level `system`, and required `max_tokens`. It adapts refac's flat message list to Anthropic's shape — lifts the system prompt out of messages and merges the consecutive user turns to satisfy user/assistant alternation — and marks the static system prompt + few-shot examples `cache_control: ephemeral` so repeat calls only pay for the varying input. Config gains `provider`, optional `model` (defaulted per provider), and `max_tokens`; secrets hold either/both keys. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Some few-shot samples have an empty `selected`; Anthropic rejects empty text content blocks (OpenAI tolerated them), so skip empty messages when building the request. Add a REFAC_DEBUG env that dumps the request JSON. Verified end-to-end: 'Me like toast.' / 'Correct grammar.' -> 'I like toast.'

…intln Per review: drop the ad-hoc REFAC_DEBUG env-gated eprintln and use the existing tracing setup, gated by the subscriber's level filter like the rest of the code. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: `provider` is now optional. When it isn't set explicitly (config file or REFAC_PROVIDER), resolve it from which keys are configured — only an OpenAI key -> OpenAI; Anthropic-only, both, or neither -> lean Anthropic. An explicit choice still wins. Adds resolve_provider() + tests. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: a `max_tokens` config knob is a representable invalid state — `provider = "openai"` + `max_tokens` does nothing (the OpenAI path ignores it). Remove it. The Messages API still requires `max_tokens`, so hardcode it as a constant in the anthropic module. Can be reintroduced later with real support in both backends. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: - REFAC_PROVIDER no longer silently falls back to Anthropic on an unrecognized value — it errors with the accepted options. - OpenAI default model o1 -> gpt-5.5 (current flagship). - Drop a WHAT doc-comment on model(). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: `refac login` now accepts `--provider anthropic|openai`; without it, the user selects a provider via a dialoguer prompt rather than the key-inference heuristic (you're choosing which key to add). Provider derives clap::ValueEnum. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

bddap · 2026-06-02T18:15:37Z

we have a merge conflict

Per review: the prompt-cache breakpoint was inferred from message structure (last assistant turn), which baked in refac's usage pattern. Take the static prefix length from the caller instead — refactor() passes chat_prefix().len(), the part that's fixed across calls. build_request places the breakpoint at that boundary and never groups a varying turn into the cached prefix. Also corrected stale comments (alternation is no longer required; merging is just grouping). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

# Conflicts: # Cargo.toml

bddap-bot · 2026-06-02T18:21:20Z

Resolved in 7268ea8 — merged main in. The only conflict was the rpassword bump (#29); took 7.5.0 and kept the new dialoguer dep. Builds + tests green; PR shows mergeable again.

Per review: that claim could go stale; omit it. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: - module doc was tmi / drifting — cut to a one-liner. - removed the verbose MAX_TOKENS comment (kept the const; the API requires the field). - replaced the stringly-typed content/cache `type` tags with enums (BlockType, CacheType). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

The match arms say it; the doc comment carries the why. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review. Also drop the WHAT comments restating the test assertions. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: drop the mirrored label array; map choices through Debug instead. Also drop a comment per suggestion. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Message is now `{ role: Role, fields: Vec<String>, cache: bool }` instead of a single-string OpenAI-shaped struct. A turn carries one or more text fields (a transform user turn is [selected, transform]); `cache` marks the last turn of a static prefix. - anthropic: each field -> a content block; empty fields render as `(empty)` (the API rejects empty text); `cache` -> cache_control on the turn's last block. Drops the old consecutive-same-role merge and the cache_prefix_len parameter — the data model carries both now. - openai: its own `OpenAiMessage` wire type; the adapter joins a turn's fields and drops `cache`. - prompt: chat_prefix marks its last message cached. Live-tested against Anthropic: a normal transform and an empty-selected generate ("find .") both work. 5 unit tests pass. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: joining a turn's fields into one string blurs the selected text into the transform with no reliable separator. Send each field as a separate message instead (same as the pre-refactor OpenAI path). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

~$2.00 of Opus 4.8 output at $25/M. Verified the API accepts it for the model. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Per review: - CacheControl and the content block are internally-tagged unions; use `#[serde(tag = "type")]` enums instead of a struct with a manual `type` field. - message roles are `Role` enums (anthropic ChatMessage and OpenAiMessage), not strings; Role gains a lowercase serde repr and `as_str` goes away. - the response block is a tagged enum (`Text { text } | Other`) rather than a stringly `kind` compared against "text". Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

api.rs is now just the provider-agnostic core (`Message`, `Role`). OpenAI's wire types and `complete` move to a new openai.rs; the Anthropic-only `field_or_placeholder` moves into anthropic.rs (and OpenAI no longer applies it — it tolerates empty content). Also drops the unused OpenAI edits-API types (EditRequest/EditResponse/Choice), which were dead. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Drop the removed `max_tokens` config setting, note provider is inferred from keys when unset, fix the API-key link to Anthropic (the default), and reword "still supported" -> "also supported". Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

bddap · 2026-06-02T20:58:35Z

Almost ready. Do a sub-agent reviewer loop, then regen the examples in readme using latest opus.

Review-loop findings: - the saved secrets file held the API key but was created world-readable (default 0644); create/force it 0600 on unix. - LogEntry.provider was a Debug-formatted string; use the Provider enum so the log matches the config-file casing and stays typed. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

bddap-bot · 2026-06-02T21:07:41Z

Done — review loop + example regen.

Sub-agent review loop (3 agents: correctness, security, design/taste) over the full diff. Fixes landed in eca0c21:

Security (the one real finding): secrets.toml was written with default perms (0644) — your API key was world-readable on a multi-user box. Now created/forced 0600 on unix.
LogEntry.provider was a format!("{:?}") string; now the Provider enum, so the log matches the config casing (anthropic, not Anthropic).

No correctness or injection bugs found. User text is serialized via serde (never concatenated into JSON), the key never hits logs or error bodies.

Judgment calls I left (flagging, not blocking — your call):

login --provider openai doesn't persist the choice; it only stores the key, and inference leans Anthropic when both keys exist — so picking OpenAI at login can be silently overridden. Could have login write provider to config. Left it as your current design + REFAC_PROVIDER escape hatch.
Message.cache is a public bool set by post-construction mutation; a .cached() builder would be tidier. Minor.
fields: Vec<String> (anonymous positional) — reviewers agreed it's acceptable given the adapters iterate fields uniformly.

README examples regenerated with Opus 4.8 (610e2db) — all 7 are fresh real outputs.

bddap-bot and others added 2 commits May 29, 2026 10:44

bddap-bot mentioned this pull request May 29, 2026

Function-call edits (structured replacements, not full rewrite) #31

Closed