fix: correct baseline_scope for scoped integrity labels and discussion tool integrity

[Copilot]

ensure_integrity_baseline ranks integrity labels by matching the baseline_scope against label scopes. When baseline_scope stays as repo_id (often empty) but integrity was assigned with a different scope, the rank comparison returns 0 and the labels get replaced by none.

Fixes

baseline_scope not set for project:github-scoped tools

project_github_label(ctx) calls writer_integrity("github", ctx), producing labels like approved:github. Without baseline_scope = "github", ensure_integrity_baseline downgrades these to none:.

Affected tools: get_me, get_teams, get_team_members, list_starred_repositories, search_orgs, list_global_security_advisories, get_global_security_advisory.

baseline_scope not set for user-scoped tools

reader_integrity("user", ctx) produces unapproved:user — same downgrade issue without baseline_scope = "user".

Affected tools: list_gists, get_gist.

Discussion tools silently producing none integrity for public repos

private_writer_integrity returns [] for public repos, which ensure_integrity_baseline converts to none. No label_response_paths/label_response_items fallback exists for these tools, so public discussion content was permanently stuck at none and filtered at any min-integrity > none. Replaced with writer_integrity(repo_id, ctx) to assign approved at the resource level unconditionally.

Affected tools: list_discussions, get_discussion, get_discussion_comments.

Test updates

• Removed repo_id = "github" / repo_id = "user" workarounds in 9 tests that were compensating for the missing baseline_scope assignments — tests now use realistic empty repo_id
• Updated discussion assertions from none_integrity → writer_integrity

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[Copilot]

Pull request overview

This PR fixes integrity label downgrades caused by ensure_integrity_baseline when tool rules emit scoped integrity labels (e.g., approved:github, unapproved:user) but baseline_scope remains the default repo_id (often empty), causing integrity to collapse to none.

Changes:

• Set baseline_scope explicitly for project:github-scoped tools and user-scoped gist tools so scoped integrity labels are preserved.
• Change discussion-related tools to assign writer_integrity at the resource level (instead of private_writer_integrity) to avoid none integrity in public repos.
• Update unit tests to remove prior repo_id = "github"/"user" workarounds and to reflect the new discussion integrity behavior.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
guards/github-guard/rust-guard/src/labels/tool_rules.rs	Aligns baseline_scope with integrity label scope for several tools; changes discussion tool integrity assignment.
guards/github-guard/rust-guard/src/labels/mod.rs	Updates tests to use realistic empty repo_id and adjusts discussion integrity expectations.

Comments suppressed due to low confidence (1)

guards/github-guard/rust-guard/src/labels/tool_rules.rs:435

• get_discussion_comments now uses writer_integrity(repo_id, ctx) for discussion comments as well. Since these are explicitly user-submitted and can be the lowest-trust content, treating them as approved at the repo scope can let untrusted public comments pass filters when min-integrity > none. A safer pattern would mirror issues: keep resource-level integrity conservative (e.g., private_writer_integrity or reader_integrity) and add response labeling to compute integrity from author association / approval labels per comment.

        "get_discussion_comments" => {
            // Discussion comments are user-submitted, lowest-trust user content.
            // S = inherits from repo visibility
            // I = approved — treat discussion comments as approved at the resource level
            secrecy = apply_repo_visibility_secrecy(&owner, &repo, repo_id, secrecy, ctx);
            integrity = writer_integrity(repo_id, ctx);

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[Copilot]

list_discussions / get_discussion now assign writer_integrity(repo_id, ctx) unconditionally. This elevates user-generated discussion content to approved integrity even for public repos, which differs from the existing approach for other user-submitted repo content (e.g., issues use private_writer_integrity + per-item issue_integrity in response labeling). Consider keeping resource-level integrity at private_writer_integrity(repo_id, repo_private, ctx) (or reader_integrity for public) and adding response labeling for discussions to compute integrity per item (similar to issue_integrity), so min-integrity policies aren’t bypassed for untrusted public content.

This issue also appears on line 430 of the same file.

See below for a potential fix:

            // I = reader — resource-level integrity reflects read access; per-item
            //     labeling should be used to elevate trusted content if needed
            secrecy = apply_repo_visibility_secrecy(&owner, &repo, repo_id, secrecy, ctx);
            integrity = reader_integrity(repo_id, ctx);
        }

        "get_discussion_comments" => {
            // Discussion comments are user-submitted, lowest-trust user content.
            // S = inherits from repo visibility
            // I = reader — resource-level integrity reflects read access; per-item
            //     labeling should be used to elevate trusted content if needed
            secrecy = apply_repo_visibility_secrecy(&owner, &repo, repo_id, secrecy, ctx);
            integrity = reader_integrity(repo_id, ctx);