feat: add topic parameter to list_projects and list_group_projects

[paolomainardi]

🤖 This was written by an AI agent on behalf of @paolomainardi.

Summary

• Adds optional topic parameter to ListProjectsSchema and ListGroupProjectsSchema in schemas.ts
• Adds the corresponding handler line in listGroupProjects() in index.ts (listProjects() already uses a generic loop that passes all schema fields through)
• The GitLab REST API supports topic on both GET /projects and GET /groups/:id/projects — this change simply exposes the existing API capability through the MCP tools

Motivation

We tag internal documentation repositories with topics (e.g. mkdocs) on GitLab and need AI agents to discover them via list_projects(topic: "mkdocs"). Currently the only workaround is execute_graphql, which is heavier and harder to guide agents toward safely.

Closes #417

Changes

schemas.ts — 2 lines added:

// In ListProjectsSchema
topic: z.string().optional().describe("Filter by topic (projects tagged with this topic)"),

// In ListGroupProjectsSchema
topic: z.string().optional().describe("Filter by topic (projects tagged with this topic)"),

index.ts — 1 line added in listGroupProjects():

if (options.topic) url.searchParams.append("topic", options.topic);

Testing

• npm run build passes (TypeScript compiles cleanly)
• No runtime behavior changes for existing callers — topic is optional and defaults to undefined

[Copilot]

Pull request overview

Exposes GitLab’s existing topic filter on project listing endpoints by adding an optional topic parameter to the MCP tool schemas and wiring it into the group-projects listing URL builder.

Changes:

• Add optional topic to ListProjectsSchema and ListGroupProjectsSchema.
• Append topic as a query parameter in listGroupProjects() when provided.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
schemas.ts	Adds topic to the Zod schemas so the MCP tool inputs accept it.
index.ts	Appends topic to the GET /groups/:id/projects query string when present.