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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds genuinely useful behavior: it discloses what the backend index is (the Legislature's own full-text index), that it matches body text rather than captions, what comes back (citations, captions, highlighted snippets, index-wide match count), and that it is keyless.

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 scope, then return shape, then the sibling route, then an optional-parameter note and an auth note — no filler sentences. It runs slightly long and duplicates query examples that already appear in the schema, which keeps it from a 5.

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 carries the burden of describing the return and does so (citations with captions, highlighted snippets, match count). Combined with the cite_prefix restriction note and the keyless statement, an agent has everything needed to invoke it correctly.

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 the baseline is 3. The description goes slightly beyond the schema by attaching domain meaning to cite_prefix ('296' for L&I, '458-20' for Revenue excise-tax rules) rather than only showing bare example values, which helps an agent pick a prefix correctly.

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 ('Search the FULL TEXT of the Washington Administrative Code') and immediately scopes it (matches rule TEXT, not just captions). It distinguishes itself from retrieval siblings by naming wa_wac_section as the citation-lookup path, so an agent can tell search apart from section fetch without opening either 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?

Gives concrete trigger examples ('workplace safety bulletin board', 'septic system permit') and routes to the alternative: 'Call wa_wac_section with a citation for the full text and history.' It does not, however, address the RCW-vs-WAC boundary implied by the sibling wa_rcw_section, so one routing decision is left to inference.

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