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

No annotations are provided, so the description carries full responsibility. It discloses that the tool only performs capability discovery and does not evaluate permits, which sets accurate expectations. It also surfaces that the tool returns idempotency and safe-writeback semantics, adding behavioral context about subsequent write operations.

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 short sentences, front-loaded with the 'Use first' directive. No filler; every phrase adds distinct information about timing, content, or scope.

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?

For a no-parameter capability-discovery tool with an output schema, the description covers what the tool does, what it returns, and what it does not do. The only omission is naming the sibling tools for permit checks, but the sibling list is available in context.

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?

The input schema has zero properties, so the description has no parameter burden. The baseline for zero-parameter tools is 4, and the description appropriately focuses on output content and usage rather than parameters.

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 action ('Use first to get') and a concrete resource list (supported Canadian cities/families, identity/idempotency, safe-writeback semantics). Explicitly distinguishes itself from permit-checking siblings by declaring 'no permit determination is performed.' An agent can immediately tell this is the capability-discovery tool, not the requirement checker.

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?

Opens with the directive 'Use first,' which tells the agent the intended call order relative to other tools. 'Capability discovery only; no permit determination is performed' clearly marks when not to use it, and the sibling names make the alternative obvious. It could have named the sibling tools explicitly, but the context is unambiguous.

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