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

The annotations already declare readOnlyHint=true, so the read-only nature is covered. The description adds that results are uncited(out_of_scope) when not covered, which is useful behavioral context. It does not detail return format specifics, but with annotations handling the safety profile, this is adequate.

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 concise, with three sentences that front-load the core purpose and then add scope details. It includes a clear example call. It could be slightly more polished by clarifying the example, but it earns its place with no wasted words.

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 the tool has 2 parameters, no output schema, and moderate annotations (readOnlyHint), the description reasonably covers the inputs and hints at the return type (topical map). It lacks details on the structure of the output or any edge cases, but for a read-only probe tool, it is sufficiently complete, though not exhaustive.

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 description coverage is 0%, so the description must compensate. It explains 'topic' as the subject of the query and 'repo' as a scope limiter, providing meaning beyond the schema. It also gives an example call with '{}', though that example is for no arguments, which is slightly misleading since 'topic' is required. Overall, it adds value for both parameters.

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 the tool's purpose: to ask the corpus about its coverage on a topic and return a topical map with citations. It distinguishes itself from sibling tools like introspection_corpus_query by focusing on scope/probe rather than general query, though it doesn't explicitly name the alternative. The verb 'probe' plus resource 'corpus' is specific.

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?

It provides some context on when to use the tool (when asking what the corpus covers on a topic) and mentions an optional 'repo' parameter to scope the question to one repo. However, it does not explicitly say when not to use this tool or mention alternatives like introspection_corpus_query, leaving the distinction implicit.

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