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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuinely non-obvious operational context: the $0.005 USDC per-call x402 cost and the fact that the two modes hit different upstream services (GovInfo vs Congress.gov). It stops short of covering rate limits, pagination, or behavior when both parameters are supplied.

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?

A single dense sentence with the resource front-loaded, followed by the two modes and then cost. Every clause carries information; the cost disclosure is last, which is acceptable but slightly less scannable than leading with capability.

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 enumerates the fields returned in bill-lookup mode, which is the key detail an agent needs. It does not characterize the search-result shape or the meaning of limit, a modest but real gap for a two-mode 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 coverage is 67%, and the description compensates for the weakest parts: it explains that q drives full-text search against GovInfo and that bill takes an id like hr1-119, including the format exemplar's meaning. The limit parameter remains undocumented in both schema and description, which keeps this below 5.

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 resource (US Congress bills) and two distinct operations: keyword search of bill text via GovInfo, and bill-id lookup returning named fields. The named output fields (title, sponsor, cosponsors, policy area, latest action) make the retrieval mode concrete and unmistakable.

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 effectively routes between the two modes by naming the parameter that selects each (q for keyword search, bill for detail) and attributing each to its backing source. It does not add explicit when-not-to-use guidance, but no sibling tool overlaps this domain, so exclusions are largely unnecessary.

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