fix: minor claude code fixes

[TejasGhatte]

Summary

Fixes two bugs in the Anthropic reverse-stream converter that caused incorrect content_block index numbering depending on the request path:

1. Passthrough path (Claude Code): The converter was unconditionally consuming (and discarding) a content-block index for dropped server-tool result blocks (web_fetch, zero-result web_search). This is correct only on the passthrough path, where verbatim raw upstream frames are interleaved and indices must stay in lockstep. On the all-normalized path, this caused a gap in indices (e.g. [0, 1, 3] instead of [0, 1, 2]), which strict Anthropic SDK clients reject as a missing block.

2. Tool version recognition: convertAnthropicToolToBifrost matched web_search and web_fetch tool types by exact version string. Any future-dated version (e.g. web_fetch_20260318) silently fell through to the client-function default instead of being recognized as a server tool.

Changes

• Introduced a passthrough bool field on anthropicToResponsesStreamState and a SetResponsesStreamPassthrough(ctx) function. The transport calls this when shouldUsePassthrough is true; the converter reads it to decide whether to consume the discarded result-block index.
• The index-consuming allocBlockIndex("") calls for web_fetch and resultless web_search are now gated on state.passthrough, keeping indices contiguous on the all-normalized path.
• convertAnthropicToolToBifrost now matches web_search_* and web_fetch_* tool types by prefix (via strings.HasPrefix) in a separate switch typeStr := string(*tool.Type); { case ... } block before the exact-match switch, so any current or future dated version is correctly recognized.
• The passthrough test harness (runAnthropicPassthrough) now calls SetResponsesStreamPassthrough to mirror what the transport does, keeping existing passthrough tests accurate.
• Added TestAnthropicConverterOnly_IndicesContiguous to assert that the all-normalized path emits contiguous content_block_start indices 0, 1, 2, … across web_fetch, zero-result web_search, and combinations thereof.
• Added TestServerSearchTools_VersionRecognition to assert that known and future-dated web_search_* / web_fetch_* tool types all map to the correct neutral server-tool type and never fall through to ResponsesToolTypeFunction.

Type of change

• Bug fix

Affected areas

• Core (Go)
• Transports (HTTP)
• Providers/Integrations

How to test

go test ./core/providers/anthropic/... -run "TestAnthropicConverterOnly_IndicesContiguous|TestServerSearchTools_VersionRecognition|TestAnthropicPassthrough|TestAnthropicConverterOnlyStream"
go test ./transports/bifrost-http/...
go test ./...

TestAnthropicConverterOnly_IndicesContiguous will fail before the fix with output like:

non-contiguous content_block_start indices [0 1 3] (position 2 is index 3, not 2); native Anthropic never skips an index

TestServerSearchTools_VersionRecognition will fail before the fix for web_search_20260318 and web_fetch_20260318 with:

neutral tool type = "function", want "web_search" (must not fall through to a client function tool)

Breaking changes

• No

Security considerations

None.

Checklist

• I read docs/contributing/README.md and followed the guidelines
• I added/updated tests where appropriate
• I updated documentation where needed
• I verified builds succeed (Go and UI)
• I verified the CI pipeline passes locally if applicable

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[coderabbitai]

📝 Walkthrough

Walkthrough

Adds an explicit passthrough mode flag to the Anthropic reverse-stream conversion state, gating content-block index allocation for web_search/web_fetch completions so indices stay aligned with raw upstream frames during passthrough and remain contiguous otherwise. Refactors tool-type matching to prefix-based recognition for versioned server tools, wires the flag from the HTTP transport, and adds regression tests.

Changes

Anthropic passthrough index alignment and tool version recognition

Layer / File(s)	Summary
Passthrough state field and setter core/providers/anthropic/responses.go	Adds a passthrough bool field to anthropicToResponsesStreamState and exported SetResponsesStreamPassthrough(ctx) to enable it on context-stored conversion state.
Gate index allocation on passthrough state core/providers/anthropic/responses.go	WebSearchCall and WebFetchCall completion handling in ToAnthropicResponsesStreamResponse now allocate/discard the extra upstream result content-block index only when state.passthrough is true, previously unconditional.
Prefix-based server tool version recognition core/providers/anthropic/responses.go, core/providers/anthropic/websearch_test.go	convertAnthropicToolToBifrost matches web_search_* and web_fetch_* tool types via strings.HasPrefix instead of enumerating version constants; a new test validates correct neutral tool-type mapping for versioned inputs.
Transport wiring and regression tests transports/bifrost-http/integrations/anthropic.go, core/providers/anthropic/passthroughstream_test.go	The Anthropic streaming passthrough branch now calls SetResponsesStreamPassthrough(ctx); the passthrough test harness always enables passthrough mode; a new test asserts contiguous content_block_start indices for the converter-only (non-passthrough) path.

Estimated code review effort: 3 (Moderate) | ~25 minutes

Possibly related PRs

• maximhq/bifrost#4890: Addresses the same Anthropic Claude Code passthrough streaming behavior for web_search/web_fetch content-block index alignment with related test coverage.

Suggested reviewers: danpiths, akshaydeo, roroghost17

🚥 Pre-merge checks | ✅ 2 | ❌ 3

❌ Failed checks (2 warnings, 1 inconclusive)

Check name	Status	Explanation	Resolution
Linked Issues check	⚠️ Warning	The PR fixes Anthropic streaming/indexing bugs, not the requested Files API support for POST /v1/files.	Implement the Files API upload workflow for OpenAI/Anthropic, or relink this PR to the correct issue.
Out of Scope Changes check	⚠️ Warning	All code changes are Anthropic converter/test fixes and do not relate to Files API support.	Remove the Anthropic-only fixes from this PR or split them into a separate PR tied to the correct issue.
Title check	❓ Inconclusive	The title is related to the PR, but it's too generic to explain the specific Anthropic converter fixes.	Use a more specific title such as "fix Anthropic content_block indexing and tool version recognition".

✅ Passed checks (2 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description check	✅ Passed	The description matches the template and covers summary, changes, testing, and checklist items, with only optional sections left blank.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch 07-05-fix_minor_claude_code_fixes

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[TejasGhatte]

• fix: minor claude code fixes #4932 👈 (View in Graphite)
• dev

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[greptile-apps]

Confidence Score: 4/5

The changes are narrowly scoped to the Claude Code passthrough streaming path and the tool-type converter; existing non-passthrough flows are unaffected and guarded by new tests.

The logic is correct and well-exercised by new tests. The one gap is a comment in convertAnthropicToolToBifrost that omits computer_use from the list of tools that stay in the exact-version switch, which could mislead a future contributor adding a new computer-use version constant.

The comment on lines 6317-6322 of core/providers/anthropic/responses.go should mention computer_use alongside code_execution and text_editor to keep the documentation accurate.

Important Files Changed

Filename	Overview
core/providers/anthropic/responses.go	Adds passthrough bool to anthropicToResponsesStreamState and gates the phantom block-index allocations for dropped web_fetch/web_search result blocks behind it; also switches convertAnthropicToolToBifrost from exact-version matching to prefix matching for web_search_/web_fetch_ tool types.
transports/bifrost-http/integrations/anthropic.go	Calls SetResponsesStreamPassthrough(ctx) at the top of the passthrough branch so the reverse converter knows to consume phantom block indices; placed before ToAnthropicResponsesStreamResponse on every code path through that branch.
core/providers/anthropic/passthroughstream_test.go	Fixes existing passthrough harness to call SetResponsesStreamPassthrough (required after the gating change) and adds TestAnthropicConverterOnly_IndicesContiguous covering the all-normalized path across five tool-combination scenarios.
core/providers/anthropic/websearch_test.go	Adds TestServerSearchTools_VersionRecognition to guard that future-dated web_search_/web_fetch_ versions (e.g. 20260318) are correctly mapped to the neutral server-tool type rather than falling through to ResponsesToolTypeFunction.

Sequence Diagram

%%{init: {'theme': 'neutral'}}%%
sequenceDiagram
    participant T as Transport (anthropic.go)
    participant C as Converter (responses.go)
    participant S as anthropicToResponsesStreamState

    Note over T,S: Per-frame callback, passthrough path (Claude Code)
    T->>S: "SetResponsesStreamPassthrough(ctx) passthrough=true"
    alt "raw frame RawResponse != nil"
        T-->>T: return raw SSE verbatim
    else converted frame mustConvertInPassthrough
        T->>C: ToAnthropicResponsesStreamResponse(ctx, resp)
        C->>S: state.passthrough true
        alt web_fetch / zero-result web_search
            C->>S: allocBlockIndex phantom keeps counter in lockstep
        end
        C-->>T: AnthropicStreamEvent slice
    end

    Note over T,S: Per-frame callback, all-normalized path curl/OpenAI-via-Anthropic
    T->>C: ToAnthropicResponsesStreamResponse(ctx, resp)
    C->>S: state.passthrough false
    Note over C: No phantom index consumed indices stay contiguous 0,1,2

Loading

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sequenceDiagram
    participant T as Transport (anthropic.go)
    participant C as Converter (responses.go)
    participant S as anthropicToResponsesStreamState

    Note over T,S: Per-frame callback, passthrough path (Claude Code)
    T->>S: "SetResponsesStreamPassthrough(ctx) passthrough=true"
    alt "raw frame RawResponse != nil"
        T-->>T: return raw SSE verbatim
    else converted frame mustConvertInPassthrough
        T->>C: ToAnthropicResponsesStreamResponse(ctx, resp)
        C->>S: state.passthrough true
        alt web_fetch / zero-result web_search
            C->>S: allocBlockIndex phantom keeps counter in lockstep
        end
        C-->>T: AnthropicStreamEvent slice
    end

    Note over T,S: Per-frame callback, all-normalized path curl/OpenAI-via-Anthropic
    T->>C: ToAnthropicResponsesStreamResponse(ctx, resp)
    C->>S: state.passthrough false
    Note over C: No phantom index consumed indices stay contiguous 0,1,2

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_{Reviews (1): Last reviewed commit: "fix: minor claude code fixes" | Re-trigger Greptile}

[coderabbitai]

🧹 Nitpick comments (1)

core/providers/anthropic/websearch_test.go (1)

296-298: 📐 Maintainability & Code Quality | 🔵 Trivial | 💤 Low value

Minor: Name: "web_fetch" reused for web_search test cases.

Every case constructs the tool with Name: "web_fetch", even the web_search_* rows. Doesn't affect correctness since convertAnthropicToolToBifrost dispatches on Type first, but it's confusing when reading/debugging a failing web_search case.

🧹 Suggested tweak

-			in := &AnthropicTool{Type: schemas.Ptr(AnthropicToolType(c.toolType)), Name: "web_fetch"}
+			in := &AnthropicTool{Type: schemas.Ptr(AnthropicToolType(c.toolType)), Name: c.toolType}

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@core/providers/anthropic/websearch_test.go` around lines 296 - 298, The test
setup in convertAnthropicToolToBifrost uses the same tool name for both
web_fetch and web_search cases, which makes the web_search scenarios harder to
read and debug. Update the AnthropicTool construction in websearch_test.go so
the name matches the case being exercised, especially in the web_search rows,
while keeping the existing Type-based dispatch unchanged. Use the
convertAnthropicToolToBifrost test table and the t.Run(c.toolType, ...) setup to
locate the shared test initializer.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@core/providers/anthropic/websearch_test.go`:
- Around line 296-298: The test setup in convertAnthropicToolToBifrost uses the
same tool name for both web_fetch and web_search cases, which makes the
web_search scenarios harder to read and debug. Update the AnthropicTool
construction in websearch_test.go so the name matches the case being exercised,
especially in the web_search rows, while keeping the existing Type-based
dispatch unchanged. Use the convertAnthropicToolToBifrost test table and the
t.Run(c.toolType, ...) setup to locate the shared test initializer.

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ℹ️ Review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 4be1d6d and 861f1c5.

📒 Files selected for processing (4)

• core/providers/anthropic/passthroughstream_test.go
• core/providers/anthropic/responses.go
• core/providers/anthropic/websearch_test.go
• transports/bifrost-http/integrations/anthropic.go

[akshaydeo]

Merge activity

• Jul 5, 9:56 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jul 5, 9:56 PM UTC: @akshaydeo merged this pull request with Graphite.