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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds genuinely useful behavior the annotations cannot: no live GitHub calls (results reflect a snapshot, not GitHub state), coverage limited to repos on a board, and deterministic ranking where exact owner/name wins. It does not discuss truncation or ordering beyond exact-match precedence, keeping it at a 4 rather than a 5.

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 compact sentences, front-loaded with what it searches and how matching works, followed by scope exclusions. No filler and nothing repeated from the schema or annotations.

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?

An output schema exists, so return values need no explanation, and the tool is a read-only search with only two parameters. The one real gap is that `limit`'s effect (pagination or truncation of results) is never described, but everything an agent needs to form a correct query is present.

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 50%: `q` is documented in the schema, while `limit` has bounds and a default but no description, and the description does not mention `limit` at all. The description does enrich `q` by explaining that an owner/name fragment beats a description keyword and that keyword matching spans 16 languages' descriptions, which is real added meaning over 'owner/name fragment or keyword'.

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 (search) and resource (repositories tracked by this site), and further specifies two matching modes with precedence: owner/name exact match wins, keyword searches descriptions across 16 languages. This is enough to tell it apart from get_repo (single fetch) and list_boards without opening either 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 a clear when-not: 'Library-only: repos never listed on a board are not here' plus 'No live GitHub calls', which tells the agent this is a cached/curated index and that unlisted repos need a different route. It stops short of naming a sibling as the alternative (e.g. read the board and use get_repo), so it is clear context rather than full routing guidance.

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