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

Annotations declare readOnlyHint and openWorldHint, so the safety profile is covered; the description adds real behavioral context beyond that: required query scope, channel-access constraint, and that the result is a generated answer with citations rather than raw chunks. It doesn't cover rate limits or top_k behavior, but the additions are substantive.

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?

Two sentences, zero waste, with the core purpose front-loaded and the REST mapping and auth requirement following in priority order.

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 carries return-value burden and does so by stating a generated answer with citations. Combined with the documented auth scope and a fully-described parameter schema, it is nearly complete; only retrieval controls (top_k defaults, session behavior) and rate/limit expectations are unaddressed.

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 100%, so every parameter is already documented in the schema, making 3 the baseline. The description adds no parameter-specific meaning (e.g., how session_id interacts with multi-turn or how source_types affects citations), so it does not exceed the baseline.

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?

Specific verb+resource: 'Run a retrieval-augmented query against a channel's indexed knowledge base and return a generated answer with citations,' plus the REST mapping POST /v1/query. It clearly conveys what the tool does, but it never explicitly distinguishes itself from the sibling query_collection beyond the word 'channel.'

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?

States a prerequisite ('Requires the key's query scope and access to the channel'), which is useful context for when the call will succeed. However, it gives no guidance on when to choose this over query_collection, nor any when-not conditions.

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