search_repositories

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

With no annotations provided, the description carries the full burden. It discloses the sort order (by stars descending), which is a key behavioral trait. However, it does not mention pagination behavior, authentication needs, or any side effects. For a read-only search tool, this is minimal but acceptable, hence a 3.

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?

The description is two sentences: the first states the core function and sorting, the second provides a concrete example. Every word earns its place, with no redundancy or filler.

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?

Given that the schema covers all parameters and an output schema exists, the description is largely complete. It explains the purpose, sorting, and typical usage. It does not explicitly mention pagination, but the schema parameters (page, per_page) imply it. Adequate for the tool's simplicity.

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?

The schema provides 100% parameter description coverage, so the description does not need to explain individual parameters. The description aligns with the min_stars parameter context but adds no new parameter-level meaning beyond what the schema already provides. Baseline 3 is appropriate.

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?

The description clearly states 'Search repositories' with the specific sorting behavior ('sorted by popularity (stars) descending'), which distinguishes it from sibling tools like search_code and search_issues. The verb and resource are explicit and unambiguous.

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?

The description provides useful usage context: 'Use this to explore existing repos and projects, e.g. find the most starred implementations of a tool or library.' This implies when to use it, but it does not explicitly mention alternatives or when not to use it. A clear context without exclusions merits a 4.

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