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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open world), so the description's added value is the cost model: $1.80 per 1,000 trades, no start fee, charged only for trades delivered, stopping at the max charge limit. It also discloses provenance (official Clerk of the House filings, PTR PDF per row) and result ordering (newest filings first). Minor gap: no mention of pagination or how partial-year coverage behaves when years are omitted.

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: the data scope leads, followed by the field list, then audience, then pricing. One waste point exists — pricing is stated twice, once as 'Pricing: $1.80 per 1,000 trades ($0.0018 per trade)' and again as 'Price: $0.0018 per `trade`.' — which is redundant rather than harmful.

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 8 optional parameters, no output schema, and annotations carrying the safety profile, the description supplies what an agent actually needs: data source, time coverage since 2014, per-row fields, sort order, and billing behavior. Pagination and behavior when filters are omitted are the only notable omissions.

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 every parameter (years, filedFrom/filedTo, members, tickers, maxResults, minAmountUsd, transactionTypes) is already documented with examples and constraints. The description adds no parameter-level meaning beyond the schema, 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 specific verb and resource ('Get congress stock trades') and immediately narrows scope to trades disclosed by US House members in Periodic Transaction Reports under the STOCK Act. The enumerated output fields (member, state/district, filing date, trade date, days to disclose, owner, ticker, asset type, transaction type, amount range, PTR PDF link) make the result shape unambiguous and separate it from securities siblings like sec_insider_trades.

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 description names an audience ('for investors, journalists and AI agents tracking congressional trading'), which implies when the tool fits, but never states when to prefer it over a sibling such as sec_insider_trades or when it is the wrong choice. No prerequisites, no exclusions, no explicit alternative routing.

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