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

Annotations already declare this as a read-only, idempotent, non-destructive local lookup, so the safety profile is covered. The description adds genuine context by saying what the payload contains (verdict, analysis, and plan-unlocked sections), implying content may be partial depending on the promoter's plan — a non-obvious behavioral detail the annotations don't carry.

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 and the id provenance front-loaded and no filler. Every clause carries information the agent needs to select and call the tool.

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 single-parameter read with annotations and an output schema in place, the description covers what the tool returns and where the id comes from. Minor gaps remain around failure behavior (e.g., unknown or expired id) and its relationship to the lookalike get_brief, but nothing essential is missing.

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 schema alone leaves 'id' undefined. The description compensates by specifying the id's provenance — it is the identifier returned by a search result — which is exactly the semantics an agent needs to supply a valid value.

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 names the specific resource (a single Promoter Brief's full text) and the input source (the id a search result returned), which is far more informative than the bare name 'fetch'. It does not, however, distinguish this from the sibling get_brief, which reads like an overlapping retrieval tool, so sibling differentiation is only partial.

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 gives clear situational guidance by tying invocation to a preceding search result ('the id a search result returned'), which tells the agent when this is the right call. It stops short of exclusions — there is no statement of when to use get_brief or list_briefs instead.

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