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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered; the description goes beyond that by disclosing the substance of the result (before/after values, observation time, source-as-of date, raw snapshot hash), signaling an audit-grade historical record. It omits ordering of transitions and how the limit interacts with completeness, so it is not fully transparent.

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?

Two tight sentences, front-loaded with the core purpose and then the returned evidence fields. Every clause carries information and there is no filler, though the second sentence is a dense field list.

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 does a reasonable job of enumerating returned fields. However, it supplies no routing guidance against the two very similar contractor-license siblings, which is the main gap an agent faces when selecting 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 both parameters (license_number, limit) are already documented in the schema, including the default of 50. The description adds only the notion of 'one license' and does not clarify transition ordering or the effect of the limit, so 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 concrete verb ('Return') and a well-scoped resource ('material status, expiration, specialty, and profile transitions observed for one Washington contractor license'), so an agent knows it retrieves a per-license change log. It does not, however, distinguish itself from the sibling wa_contractor_recent_changes, which an agent could easily confuse with it.

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?

There is no explicit guidance on when to use this versus wa_contractor_recent_changes (a change feed) or wa_contractor_verify (a point-in-time check). The phrase 'for one Washington contractor license' implies single-license lookup, but the choice among the three siblings is left entirely to inference.

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