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

Annotations cover the safety profile (readOnly, idempotent, non-destructive), and the description layers on behavior beyond them: response size (~4 KB JSON), error semantics for unknown codes, no-key public access, and the crucial caveat that it is editorial reference rather than a calculation engine.

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 what it returns before the routing guidance and caveats, and every clause carries real information. It is dense with several distinct ideas packed into one paragraph, which costs a bit of scannability but wastes nothing.

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 still enumerates the returned fields and their rough size, states error behavior, disclaims calculation duty, and notes public read-only access. Nothing an agent needs to select or invoke it correctly 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 single param is fully documented there, so the baseline is 3; the description adds value by pointing the agent at list_state_lien_guides as the source of valid codes and warning that unknown codes error out, which clarifies valid-value discovery beyond the schema.

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 (returns) and resource (editorial mechanics lien and preliminary notice guide for one state or DC), then enumerates the payload fields (rules, deadline_rows, faqs, source_url). An agent can distinguish it from calculate_supplier_deadlines and list_state_lien_guides without opening any schema.

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?

Explicit when-to-use triggers ('user asks how a state's lien or notice rules work, why a deadline falls where it does, or which statute applies'), a named prerequisite (call list_state_lien_guides first for codes), and a named alternative with an explicit exclusion ('Do not derive filing dates from the day counts; use calculate_supplier_deadlines').

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