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

Annotations already mark this as a read-only, idempotent, non-destructive lookup, and the description adds substantial domain behavior beyond that: whole-report versus per-issue amounts, in-house expenses vs outside-firm income that must not be summed, excluded subcontract income, null-not-zero semantics, and that filings don't establish a client's position or policy outcomes. It even names what is returned (retrieval date and LDA disclaimer). This is exactly the kind of interpretive context the agent cannot get from structured fields.

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 verb and resource, then a sequence of short caveat sentences that each carry a distinct fact. It is dense but not padded; the only redundancy is the 'missing client is not proof' line, which duplicates the parameter schema.

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 takes responsibility for describing the return (retrieval date, LDA source disclaimer) and for the aggregation rules an agent would otherwise misread. For a single-parameter lookup tool, nothing material 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 coverage is 100% and the description's 'published key or a case-insensitive name substring' restates what the parameter already documents. The one added concept, that a miss is not evidence of no lobbying, is also already in the schema text. Baseline 3 is appropriate.

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: returns client timelines from the MORVS Influence Register, keyed by published key or case-insensitive name substring. It also scopes the dataset narrowly (only reports with an AI, surveillance or privacy match). It does not explicitly differentiate itself from siblings like lobbying_by_client or lobbying_by_issue, so it stops short of a 5.

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 coverage caveat ('includes only reports with an AI, surveillance or privacy match... not a client's complete lobbying history') is an effective when-not signal, and 'a missing client is not proof of no lobbying' tells the agent how to interpret an empty result. No alternative tool is named, so the agent must infer whether lobbying_by_client is the better route.

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