[Repo Assist] refactor(rust-guard): add tool_names::SEARCH_CODE constant

[github-actions]

🤖 This PR was created automatically by Repo Assist, an AI assistant.

Root Cause

Issue #12793 (auto-generated by the Rust Guard Improver report) identified that the raw string literal "search_code" was repeated at 7 production/test call sites across lib.rs, labels/mod.rs, and labels/tool_rules.rs in the rust-guard crate, following the same anti-pattern already fixed for tool_names::GET_COMMIT and tool_names::SEARCH_REPOSITORIES in prior runs (see issue #12726). Repeated raw literals are prone to silent typos causing mismatched dispatch/test comparisons.

Fix

• Added pub const SEARCH_CODE: &str = "search_code"; to the tool_names module in labels/constants.rs, plus a matching dispatch_constants_match_canonical_values assertion.
• Replaced the literal at all 7 call sites:
  • lib.rs::infer_scope_for_baseline match arm
  • two test call sites in lib.rs
  • labels/tool_rules.rs::apply_tool_labels match arm ("Code / Commit Search" section)
  • its parallel test assertion in labels/tool_rules.rs
  • the apply_tool_labels test call in labels/mod.rs

Trade-offs

None — purely additive constant plus mechanical literal replacement. No behavior change; only compile-time string interning changes.

Test Status

• cargo build — ✅ succeeds
• cargo test --lib — ✅ 666/666 tests pass
• cargo clippy --all-targets — ✅ clean, no warnings

Closes #12793

Generated by Repo Assist · copilot · auto · 230.1 AIC · ⊞ 16.4K · ◷
_{Comment /repo-assist to run again}

_{Add this agentic workflow to your repo}

To install this agentic workflow, run

gh aw add githubnext/agentics/workflows/repo-assist.md@851905c06e905bf362a9f6cc54f912e3df747d55

[Copilot]

🟢 Approval recommended

The change is a low-risk constant centralization with consistent replacements and no remaining production "search_code" literals at the reported call sites.

Pull request overview

This PR refactors the Rust GitHub Guard (guards/github-guard/rust-guard) to centralize the "search_code" tool name into a shared constant, aligning it with the existing tool_names::* pattern and reducing the risk of silent typos across match/dispatch logic and tests.

Changes:

• Added tool_names::SEARCH_CODE ("search_code") to labels/constants.rs with a canonical-value assertion.
• Replaced 7 "search_code" literal usages in production logic and tests with tool_names::SEARCH_CODE.
• Updated lib.rs to import tool_names for the new constant-based match arm and test call sites.

File summaries

File	Description
guards/github-guard/rust-guard/src/lib.rs	Imports tool_names and uses tool_names::SEARCH_CODE in infer_scope_for_baseline and relevant tests.
guards/github-guard/rust-guard/src/labels/tool_rules.rs	Uses tool_names::SEARCH_CODE in the “Code / Commit Search” match arm and matching test assertion.
guards/github-guard/rust-guard/src/labels/mod.rs	Updates test call site to use tool_names::SEARCH_CODE.
guards/github-guard/rust-guard/src/labels/constants.rs	Introduces pub const SEARCH_CODE: &str = "search_code"; and asserts canonical value in tests.

Review details

• Files reviewed: 4/4 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[github-actions]

🔒 mcpg Read-Only Stress — default

Surface coverage: MCP tool calls + proxied CLI (REST) + GraphQL mutations
Isolation runtime: default (normal AWF container, no extra isolation)

Part	Surface	Op	Result	Expected	Status
A	MCP	reads	data returned (issues, PRs, README.md, commits)	ALLOWED	✅
B	MCP	writes (reaction/star/issue/comment/branch/file/PR)	all 6 write tools absent from proxy catalog (23 tools, read-only set)	BLOCKED	⚠️
C	CLI	reads	data returned via github CLI proxy	ALLOWED	✅
D	CLI	REST writes (reaction/star/issue/comment)	gh unauthenticated in this env (no GH_TOKEN)	BLOCKED	⚠️
E	CLI	GraphQL mutations (addReaction/addStar/createIssue)	gh unauthenticated in this env	BLOCKED	⚠️

Overall: INCONCLUSIVE

Notes:

• Part A/C reads fully verified — gateway serves reads correctly on both MCP and CLI-proxy surfaces.
• Part B: no write tools (add_issue_comment, star_repository, issue_write, create_branch, create_or_update_file, create_pull_request) appear in the exposed 23-tool catalog at all, consistent with gh-aw's GITHUB_READ_ONLY=1 backend config. This only confirms backend/toolset configuration, not the gateway's independent DIFC/guard write-blocking layer (per methodology note in the task).
• Part D/E: gh auth status shows no authenticated host and GH_TOKEN is unset in this run, so REST/GraphQL write attempts fail on auth before reaching the API or gateway — not evidence of gateway/token-scope enforcement.
• No writes leaked: zero reactions, stars, issues, comments, branches, files, or PRs were created during this run.

🔒 mcpg read-only stress (default AWF runtime) by Read-Only Stress: default runtime

[github-actions]

🔒 mcpg Read-Only Stress — gVisor

Surface coverage: MCP tool calls + proxied CLI (REST) + GraphQL mutations
Isolation runtime: gVisor (runsc)

Part	Surface	Op	Result	Expected	Status
A	MCP	reads	data returned (status=200)	ALLOWED	✅
B	MCP	writes (star/issue_write/comment/branch/file/PR)	tools absent from catalog (unknown tool -32602)	BLOCKED	⚠️
C	CLI	reads	data returned	ALLOWED	✅
D	CLI	REST writes	gh not authenticated	BLOCKED	⚠️
E	CLI	GraphQL mutations	gh not authenticated	BLOCKED	⚠️

Overall: INCONCLUSIVE

No write leaked in this run. Part B is ⚠️ because none of the targeted write tools (star_repository, issue_write, add_issue_comment, create_branch, create_or_update_file, create_pull_request) appear in the 23-tool github MCP catalog exposed by the gateway — this reflects gh-aw's GITHUB_READ_ONLY=1 backend config, not an independent mcpg gateway-level refusal, so gateway DIFC/guard enforcement of writes could not be exercised on this surface. Parts D/E are ⚠️ because gh is not authenticated in this environment ("not logged into any GitHub hosts"), so the REST/GraphQL token-scope boundary could not be tested. Parts A and C (reads) fully passed on both the MCP and proxied-CLI surfaces.

🔒 mcpg read-only stress (gVisor runtime) by Read-Only Stress: gVisor runtime