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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds genuinely useful behavior: `include` pulls parent chains, and brand mentions/citations are deliberately absent from the payload, which is exactly the kind of omission an agent would otherwise discover by failure.

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 short sentences, zero filler, and the core fetch semantics are front-loaded before the two caveats. Every sentence carries information the agent needs.

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?

No output schema exists, so the description carries some of the return-shape burden, and it does address that partially by disclosing what is not embedded. It stops short of describing the response envelope or pagination, but for a two-parameter single-fetch tool with full schema coverage this is nearly complete.

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 the baseline is 3. The description goes slightly beyond the schema's enumeration by characterizing `include` as loading 'parent chains' — explaining the intent of the whitelisted traversal rather than just listing resource names.

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 (fetch) plus resource (a single AI response) and a stated key (numeric id). It is clearly the singular counterpart to the sibling list-responses-tool, so the agent can distinguish them without opening a 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?

It states when to use `include` (to load parent chains) and explicitly routes brand mentions and citations to `/v1/brand-mentions` and `/v1/citations` rather than this tool. That is real routing guidance, though it never states the condition for choosing this tool over list-responses-tool.

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