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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds useful domain context (which AI engines are queried, that topic_ids are returned) but says nothing about pagination, ordering, or what a brand with no topics returns. With annotations carrying the behavioral load, a 3 is right.

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 tight sentences with the resource statement front-loaded and the downstream consumer (create_prompt's topic_id) trailing. Nothing is redundant or padded.

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?

For a one-parameter read tool with no output schema, the description conveys what the tool returns (topics/buyer questions per AI engine) and the key returned field (topic_id). It stops short of describing the shape of each topic entry, but the essentials for correct invocation and follow-up are 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 description coverage is 100% and the single brand_id parameter is fully documented in the schema, including the 'may be omitted for single-brand workspaces' rule. The description adds no parameter-level detail beyond that, so the baseline 3 applies.

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 concrete resource (the topics and buyer questions Proofsource tracks) and the scope (per brand, across four named AI engines), so the agent knows exactly what comes back. It does not explicitly contrast itself with a sibling like create_prompt as an alternative, but the resource is specific enough to be distinguishable.

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 clause 'Gives the topic_id create_prompt needs' supplies a clear when-to-use trigger and chains this tool to the correct next sibling. There are no explicit exclusions or edge conditions, but the workflow context is unambiguous.

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