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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds a genuinely non-obvious corpus constraint ('Corpus is 2026-forward only') and the returned field set. It stops short of explaining what match_score means (presumably 0-1 similarity) or any pagination/ranking behavior, so a 4 rather than a 5.

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?

Purpose and sibling routing are front-loaded, and the trailing status_id/bucket block earns its length because the schema has zero enums and there is no output schema. It is dense but not padded; the only redundancy is a 'match_score' mentioned up front and then absent from the enumerated return fields.

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 compensates by enumerating returned fields and decoding status_id values including the resolution edge case (bill_type_id 2) and the passed/failed/alive aggregate buckets. Combined with the corpus scope limit, an agent has everything needed to call and interpret this tool.

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 earns one step above baseline by illustrating the form the 'query' parameter should take (topical natural-language phrases rather than keywords or bill numbers), which the schema's 'The question or description, in plain English' only asserts.

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?

Opens with a specific verb+resource ('Vector search over the full text of every bill') and includes the endpoint. The plain-English query examples ('protecting kids from social media') make the retrieval mode unmistakable and distinguish it from structured or keyword siblings.

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?

Explicitly routes between three competing search tools: 'Prefer this over search_bills for questions and topics; prefer search_bills for a known bill number, sponsor, or status filter, and keyword_search_bills for exact terms that must all appear.' Both the when and the when-not are spelled out with the selecting condition.

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