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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable context beyond those hints: it enumerates the return payload, states a preference for jurisdiction-verified rules, and discloses fidelity differences ('Seattle is full SDCI fidelity, other 9 verified cities are wa-baseline-stub'). This is meaningful but not exhaustive, so a 4 is appropriate.

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?

The description is dense but efficient: it front-loads the core purpose, lists return contents, gives example usage, and then explains the special address behavior. Every sentence earns its place, though some jargon like 'wa-baseline-stub' and 'unified permit engine' adds complexity without fully clarifying.

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?

Given the output schema exists and the annotations are rich, the description is nearly complete for selection and invocation. It explains what the tool returns, when to use it, and the key address-dependent behavior. It could be more explicit about default jurisdiction behavior or the role of limit, but those are covered by the schema and are not major gaps.

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 each parameter is already documented in the schema. The description mostly restates the address behavior already captured in the schema ('when provided, the response includes `submittals_v2`') and does not add new meaning for projectType, limit, or the deck parameters. Baseline 3 is correct.

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?

The description states a specific action ('Check whether a residential construction project... requires a permit'), names the geographic scope (King/Pierce/Snohomish counties), and lists concrete return items. The 'Use for...' examples make the intended query patterns unmistakable and help distinguish this tool from broader permit-related siblings like answer_permit_question.

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 gives explicit example queries ('Do I need a permit to build a deck in Seattle?') and a clear behavioral note ('Pass `address` to also receive...'). It does not explicitly name alternative tools or state when not to use it, so it stops short of a full 5, but the usage context is clear.

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