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

Annotations only declare readOnlyHint=true, so the description carries the rest and does so well: it is FREE, anonymous callers get everything except incumbent name and evidence link, `withheld_reason` explains the omission and must be relayed verbatim, and `confidence` is explicitly 'a vocabulary, not a score'. It also commits that windows are 'never invented', which prevents an agent from fabricating precision.

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?

Front-loaded with the one-line definition and the routing sentence before any parameter detail, and every sentence carries distinct information. It is dense and the all-caps emphasis is heavy, but nothing is redundant or padding.

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?

Despite an output schema existing, the description adds what the schema cannot: the shape of results, the `derived` label, the confidence vocabulary, and the authentication-dependent redaction. For a zero-required-param discovery tool with no schema documentation, an agent has everything needed to call and interpret it.

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, and it does for four of six parameters: `kind`'s three values, `jurisdiction`'s ten values, `window_before` as an ISO date with 'window starts on or before it' semantics, and `q` searching subject/buyer/incumbent. `buyer` and `limit` are never explained, which is the only gap.

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 opening line defines the resource precisely and positions it against siblings: signals are 'what may be tendered before it is', which is exactly the distinction from find_tenders/match_tenders. The three `kind` values are enumerated with parenthetical definitions, so an agent knows the exact scope without opening the 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?

'USE THIS WHEN someone asks what is coming' plus three concrete example queries gives strong positive routing. It never states when NOT to use it or names a sibling as the alternative, so the exclusions are left to inference, keeping it at 4 rather than 5.

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