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

With no annotations, the description carries the full behavioral burden and does well: 'deterministic' implies stable output, 'public' suggests no auth barrier, and 'No network call' signals a pure computation with no side effects. It doesn't describe URL format or failure behavior, but for a simple link generator this is solid coverage.

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 sentences with no filler. The main purpose is front-loaded, and the key behavioral caveat ('No network call') is placed in the second sentence without redundancy.

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 one-parameter tool with 100% schema coverage and no output schema, the description is mostly complete: it states what is returned, for what input, and that no network call occurs. The main gap is that it doesn't explicitly position the tool relative to the sibling operations that may appear similar.

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%: the ecz_id parameter already includes a pattern, maxLength, and an example. The description does not add parameter-specific semantics, but no additional guidance is required; this matches the baseline for fully schema-documented 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?

The description opens with a specific verb ('Return'), names the exact resource (ECZ-ID), and specifies the output type (proof/re-check URL). It also adds a distinguishing property, 'No network call,' which separates it from resolution-style siblings like resolve_identity or create_request_to_resolve.

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?

'No network call' gives useful context for choosing this tool, but the description does not explicitly say when to use this tool versus sibling tools or when not to use it. Usage guidance is therefore implied rather than stated.

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