feat: Add search commit tool (#2284)

* add `SearchCommits` tool

* run test

* run script/generate-docs

* Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* refactor(search_commits): share commit conversion, surface repo, tighten query docs

- Extract newMinimalCommitFromCore to share field mapping between
  convertToMinimalCommit (RepositoryCommit) and the new
  convertCommitResultToMinimalCommit (CommitResult), removing ~50
  lines of duplicated logic from the search_commits handler.
- Add MinimalRepoRef and a search-only MinimalCommitSearchItem type
  (embedding MinimalCommit) so cross-repo commit search results
  identify the repo each commit came from. Keeping the field off
  MinimalCommit avoids paying for a never-populated field on the
  get_commit/list_commits output types.
- Rewrite the query description to teach the model the actual
  commit-search qualifier surface (repo:/org:/user: scoping, author/
  committer/date qualifiers, hash/tree/parent, merge:, is:public)
  and reword the sort description to drop redundancy with the enum.
- Extend tests to assert the repository field is surfaced and to
  cover commits with no resolved GitHub user (nil Author/Committer).
- Refresh README and toolsnap.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Sam Morrow <info@sam-morrow.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 4 people

pkg/github/__toolsnaps__/search_commits.snap

@@ -0,0 +1,47 @@
+{
+  "annotations": {
+    "readOnlyHint": true,
+    "title": "Search commits"
+  },
+  "description": "Search for commits across GitHub repositories using GitHub's commit search syntax. Useful for finding specific changes, authors, or messages across one or many repositories. Searches the default branch only.",
+  "inputSchema": {
+    "properties": {
+      "order": {
+        "description": "Sort order",
+        "enum": [
+          "asc",
+          "desc"
+        ],
+        "type": "string"
+      },
+      "page": {
+        "description": "Page number for pagination (min 1)",
+        "minimum": 1,
+        "type": "number"
+      },
+      "perPage": {
+        "description": "Results per page for pagination (min 1, max 100)",
+        "maximum": 100,
+        "minimum": 1,
+        "type": "number"
+      },
+      "query": {
+        "description": "Commit search query (GitHub commit search REST). Searches commit messages on the default branch only. Scope the search with `repo:owner/repo`, `org:`, or `user:` (queries without a scope qualifier match across all of GitHub and are usually not what you want). Other qualifiers: `author:`, `committer:`, `author-name:`, `committer-name:`, `author-email:`, `committer-email:`, `author-date:`, `committer-date:` (supports `\u003e`, `\u003c`, `\u003e=`, `\u003c=`, and `YYYY-MM-DD..YYYY-MM-DD` ranges), `merge:true|false`, `hash:`, `tree:`, `parent:`, `is:public`. Examples: `repo:owner/repo fix panic`; `org:github author:defunkt committer-date:\u003e=2024-01-01`; `\"refactor cache\" repo:o/r`; `hash:abc1234 repo:o/r`.",
+        "type": "string"
+      },
+      "sort": {
+        "description": "Sort by author or committer date (defaults to best match)",
+        "enum": [
+          "author-date",
+          "committer-date"
+        ],
+        "type": "string"
+      }
+    },
+    "required": [
+      "query"
+    ],
+    "type": "object"
+  },
+  "name": "search_commits"
+}

pkg/github/helper_test.go

@@ -139,6 +139,7 @@ const (
 	GetSearchIssues       = "GET /search/issues"
 	GetSearchUsers        = "GET /search/users"
 	GetSearchRepositories = "GET /search/repositories"
+	GetSearchCommits      = "GET /search/commits"
 
 	// Raw content endpoints (used for GitHub raw content API, not standard API)
 	// These are used with the raw content client that interacts with raw.githubusercontent.com

pkg/github/minimal_types.go

@@ -129,6 +129,23 @@ type MinimalCommit struct {
 	Files     []MinimalCommitFile `json:"files,omitempty"`
 }
 
+// MinimalRepoRef is a lightweight reference to a repository, used when a
+// result needs to identify which repository it belongs to (for example, in
+// cross-repo commit search results).
+type MinimalRepoRef struct {
+	FullName string `json:"full_name"`
+	HTMLURL  string `json:"html_url,omitempty"`
+	Private  bool   `json:"private,omitempty"`
+}
+
+// MinimalCommitSearchItem extends MinimalCommit with the containing
+// repository, since commit search spans repositories and callers need to
+// know which repo each result came from.
+type MinimalCommitSearchItem struct {
+	MinimalCommit
+	Repository *MinimalRepoRef `json:"repository,omitempty"`
+}
+
 // MinimalRelease is the trimmed output type for release objects.
 type MinimalRelease struct {
 	ID          int64        `json:"id"`
@@ -244,6 +261,13 @@ type MinimalIssueComment struct {
 	UpdatedAt         string            `json:"updated_at,omitempty"`
 }
 
+// MinimalSearchCommitsResult is the trimmed output type for commit search results.
+type MinimalSearchCommitsResult struct {
+	TotalCount        int                       `json:"total_count"`
+	IncompleteResults bool                      `json:"incomplete_results"`
+	Items             []MinimalCommitSearchItem `json:"items"`
+}
+
 // MinimalFileContentResponse is the trimmed output type for create/update/delete file responses.
 type MinimalFileContentResponse struct {
 	Content *MinimalFileContent `json:"content,omitempty"`
@@ -649,57 +673,73 @@ func convertToMinimalUser(user *github.User) *MinimalUser {
 	}
 }
 
-// convertToMinimalCommit converts a GitHub API RepositoryCommit to MinimalCommit
-func convertToMinimalCommit(commit *github.RepositoryCommit, includeDiffs bool) MinimalCommit {
+// newMinimalCommitFromCore builds a MinimalCommit from the fields that are
+// shared between *github.RepositoryCommit and *github.CommitResult. Caller
+// is responsible for setting any type-specific extras (stats/files for
+// RepositoryCommit, repository for CommitResult).
+func newMinimalCommitFromCore(sha, htmlURL string, commit *github.Commit, author, committer *github.User) MinimalCommit {
 	minimalCommit := MinimalCommit{
-		SHA:     commit.GetSHA(),
-		HTMLURL: commit.GetHTMLURL(),
+		SHA:     sha,
+		HTMLURL: htmlURL,
 	}
 
-	if commit.Commit != nil {
+	if commit != nil {
 		minimalCommit.Commit = &MinimalCommitInfo{
-			Message: commit.Commit.GetMessage(),
+			Message: commit.GetMessage(),
 		}
 
-		if commit.Commit.Author != nil {
+		if commit.Author != nil {
 			minimalCommit.Commit.Author = &MinimalCommitAuthor{
-				Name:  commit.Commit.Author.GetName(),
-				Email: commit.Commit.Author.GetEmail(),
+				Name:  commit.Author.GetName(),
+				Email: commit.Author.GetEmail(),
 			}
-			if commit.Commit.Author.Date != nil {
-				minimalCommit.Commit.Author.Date = commit.Commit.Author.Date.Format(time.RFC3339)
+			if commit.Author.Date != nil {
+				minimalCommit.Commit.Author.Date = commit.Author.Date.Format(time.RFC3339)
 			}
 		}
 
-		if commit.Commit.Committer != nil {
+		if commit.Committer != nil {
 			minimalCommit.Commit.Committer = &MinimalCommitAuthor{
-				Name:  commit.Commit.Committer.GetName(),
-				Email: commit.Commit.Committer.GetEmail(),
+				Name:  commit.Committer.GetName(),
+				Email: commit.Committer.GetEmail(),
 			}
-			if commit.Commit.Committer.Date != nil {
-				minimalCommit.Commit.Committer.Date = commit.Commit.Committer.Date.Format(time.RFC3339)
+			if commit.Committer.Date != nil {
+				minimalCommit.Commit.Committer.Date = commit.Committer.Date.Format(time.RFC3339)
 			}
 		}
 	}
 
-	if commit.Author != nil {
+	if author != nil {
 		minimalCommit.Author = &MinimalUser{
-			Login:      commit.Author.GetLogin(),
-			ID:         commit.Author.GetID(),
-			ProfileURL: commit.Author.GetHTMLURL(),
-			AvatarURL:  commit.Author.GetAvatarURL(),
+			Login:      author.GetLogin(),
+			ID:         author.GetID(),
+			ProfileURL: author.GetHTMLURL(),
+			AvatarURL:  author.GetAvatarURL(),
 		}
 	}
 
-	if commit.Committer != nil {
+	if committer != nil {
 		minimalCommit.Committer = &MinimalUser{
-			Login:      commit.Committer.GetLogin(),
-			ID:         commit.Committer.GetID(),
-			ProfileURL: commit.Committer.GetHTMLURL(),
-			AvatarURL:  commit.Committer.GetAvatarURL(),
+			Login:      committer.GetLogin(),
+			ID:         committer.GetID(),
+			ProfileURL: committer.GetHTMLURL(),
+			AvatarURL:  committer.GetAvatarURL(),
 		}
 	}
 
+	return minimalCommit
+}
+
+// convertToMinimalCommit converts a GitHub API RepositoryCommit to MinimalCommit
+func convertToMinimalCommit(commit *github.RepositoryCommit, includeDiffs bool) MinimalCommit {
+	minimalCommit := newMinimalCommitFromCore(
+		commit.GetSHA(),
+		commit.GetHTMLURL(),
+		commit.Commit,
+		commit.Author,
+		commit.Committer,
+	)
+
 	// Only include stats and files if includeDiffs is true
 	if includeDiffs {
 		if commit.Stats != nil {
@@ -728,6 +768,31 @@ func convertToMinimalCommit(commit *github.RepositoryCommit, includeDiffs bool)
 	return minimalCommit
 }
 
+// convertCommitResultToMinimalCommit converts a GitHub API commit search
+// result, attaching the containing repository so the caller can tell which
+// repo each result came from.
+func convertCommitResultToMinimalCommit(commit *github.CommitResult) MinimalCommitSearchItem {
+	item := MinimalCommitSearchItem{
+		MinimalCommit: newMinimalCommitFromCore(
+			commit.GetSHA(),
+			commit.GetHTMLURL(),
+			commit.Commit,
+			commit.Author,
+			commit.Committer,
+		),
+	}
+
+	if commit.Repository != nil {
+		item.Repository = &MinimalRepoRef{
+			FullName: commit.Repository.GetFullName(),
+			HTMLURL:  commit.Repository.GetHTMLURL(),
+			Private:  commit.Repository.GetPrivate(),
+		}
+	}
+
+	return item
+}
+
 // MinimalPageInfo contains pagination cursor information.
 type MinimalPageInfo struct {
 	HasNextPage     bool   `json:"hasNextPage"`

pkg/github/search.go

@@ -430,3 +430,109 @@ func SearchOrgs(t translations.TranslationHelperFunc) inventory.ServerTool {
 		},
 	)
 }
+
+// SearchCommits creates a tool to search for commits across GitHub repositories.
+func SearchCommits(t translations.TranslationHelperFunc) inventory.ServerTool {
+	schema := &jsonschema.Schema{
+		Type: "object",
+		Properties: map[string]*jsonschema.Schema{
+			"query": {
+				Type:        "string",
+				Description: "Commit search query (GitHub commit search REST). Searches commit messages on the default branch only. Scope the search with `repo:owner/repo`, `org:`, or `user:` (queries without a scope qualifier match across all of GitHub and are usually not what you want). Other qualifiers: `author:`, `committer:`, `author-name:`, `committer-name:`, `author-email:`, `committer-email:`, `author-date:`, `committer-date:` (supports `>`, `<`, `>=`, `<=`, and `YYYY-MM-DD..YYYY-MM-DD` ranges), `merge:true|false`, `hash:`, `tree:`, `parent:`, `is:public`. Examples: `repo:owner/repo fix panic`; `org:github author:defunkt committer-date:>=2024-01-01`; `\"refactor cache\" repo:o/r`; `hash:abc1234 repo:o/r`.",
+			},
+			"sort": {
+				Type:        "string",
+				Description: "Sort by author or committer date (defaults to best match)",
+				Enum:        []any{"author-date", "committer-date"},
+			},
+			"order": {
+				Type:        "string",
+				Description: "Sort order",
+				Enum:        []any{"asc", "desc"},
+			},
+		},
+		Required: []string{"query"},
+	}
+	WithPagination(schema)
+
+	return NewTool(
+		ToolsetMetadataRepos,
+		mcp.Tool{
+			Name:        "search_commits",
+			Description: t("TOOL_SEARCH_COMMITS_DESCRIPTION", "Search for commits across GitHub repositories using GitHub's commit search syntax. Useful for finding specific changes, authors, or messages across one or many repositories. Searches the default branch only."),
+			Annotations: &mcp.ToolAnnotations{
+				Title:        t("TOOL_SEARCH_COMMITS_USER_TITLE", "Search commits"),
+				ReadOnlyHint: true,
+			},
+			InputSchema: schema,
+		},
+		[]scopes.Scope{scopes.Repo},
+		func(ctx context.Context, deps ToolDependencies, _ *mcp.CallToolRequest, args map[string]any) (*mcp.CallToolResult, any, error) {
+			query, err := RequiredParam[string](args, "query")
+			if err != nil {
+				return utils.NewToolResultError(err.Error()), nil, nil
+			}
+			sort, err := OptionalParam[string](args, "sort")
+			if err != nil {
+				return utils.NewToolResultError(err.Error()), nil, nil
+			}
+			order, err := OptionalParam[string](args, "order")
+			if err != nil {
+				return utils.NewToolResultError(err.Error()), nil, nil
+			}
+			pagination, err := OptionalPaginationParams(args)
+			if err != nil {
+				return utils.NewToolResultError(err.Error()), nil, nil
+			}
+
+			opts := &github.SearchOptions{
+				Sort:  sort,
+				Order: order,
+				ListOptions: github.ListOptions{
+					Page:    pagination.Page,
+					PerPage: pagination.PerPage,
+				},
+			}
+
+			client, err := deps.GetClient(ctx)
+			if err != nil {
+				return utils.NewToolResultErrorFromErr("failed to get GitHub client", err), nil, nil
+			}
+			result, resp, err := client.Search.Commits(ctx, query, opts)
+			if err != nil {
+				return ghErrors.NewGitHubAPIErrorResponse(ctx,
+					fmt.Sprintf("failed to search commits with query '%s'", query),
+					resp,
+					err,
+				), nil, nil
+			}
+			defer func() { _ = resp.Body.Close() }()
+
+			if resp.StatusCode != http.StatusOK {
+				body, err := io.ReadAll(resp.Body)
+				if err != nil {
+					return utils.NewToolResultErrorFromErr("failed to read response body", err), nil, nil
+				}
+				return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to search commits", resp, body), nil, nil
+			}
+
+			minimalCommits := make([]MinimalCommitSearchItem, 0, len(result.Commits))
+			for _, commit := range result.Commits {
+				minimalCommits = append(minimalCommits, convertCommitResultToMinimalCommit(commit))
+			}
+
+			minimalResult := &MinimalSearchCommitsResult{
+				TotalCount:        result.GetTotal(),
+				IncompleteResults: result.GetIncompleteResults(),
+				Items:             minimalCommits,
+			}
+
+			r, err := json.Marshal(minimalResult)
+			if err != nil {
+				return utils.NewToolResultErrorFromErr("failed to marshal response", err), nil, nil
+			}
+
+			return utils.NewToolResultText(string(r)), nil, nil
+		},
+	)
+}