Search repositories

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare readOnlyHint/openWorldHint; the description adds substantial behavioral context beyond them: AND semantics for topics, archived/fork exclusion defaults, that open issues and PRs are counted together, and that the response echoes the exact GitHub query and total match count. These are exactly the non-obvious traits an agent needs before calling.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three paragraphs, front-loaded with purpose then matching rules then result shape, and every paragraph carries usable information. There is mild redundancy: the query qualifier catalogue appears both in the description and verbatim in the 'query' schema field.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description correctly compensates by enumerating the returned fields (full_name, stars, forks, language, license, push date, flags, topics, URL) plus the echoed query and total count. For a 12-parameter, all-optional search tool this covers everything needed to construct a call and interpret the response.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 92%, so the baseline is 3; the description still adds value by tying parameters to behavior — the archived-exclusion default behind include_archived, the strict AND rule for topics, and the fallback sort behavior (stars vs best-match). It largely restates the query qualifier list already in the schema, which caps this at 4 rather than 5.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Search public GitHub repositories') and even names the backing endpoint (GET /search/repositories). The scope — public repos only, keyword/topic/language/stars/date/license filters — is precise enough to separate it from search_code, search_issues_and_prs and get_repository without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete conditional routing: 'If you are unsure of exact topic names, call search_topics first,' plus explicit default behaviors (archived excluded unless include_archived, forks excluded by GitHub default). It does not contrast against get_repository or find_similar_repositories, so routing is clear for the main ambiguity but not exhaustive.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.