Validate CIMS ID

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

Annotations already declare readOnlyHint, openWorldHint=false, and idempotentHint, so the safety profile is covered. The description adds useful behavioral detail beyond annotations by stating it is a pure format check with no directory access, which clarifies network/side-effect behavior.

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 carry exactly the needed information: what the tool does, what format it expects, and what it does not do. Every phrase earns its place and the most important behavior is front-loaded.

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 single-parameter, read-only, idempotent validation tool, the description is nearly complete. The only minor gap is that it does not state the return/error behavior for malformed IDs, but given the simplicity and annotations, the definition is sufficient for correct selection and invocation.

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 0%, so the description must compensate for the single 'id' parameter. It does so by explaining the expected CIMS ID composition ('R-institution-account') and that the tool parses its parts, giving meaning beyond the bare minLength constraint.

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 verb ('Check whether'), a specific resource ('CIMS ID'), and a concrete shape ('R-institution-account'), adding that it parses the parts. The 'Pure format check' phrasing clearly distinguishes it from the directory-related sibling tools like cims_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?

The description gives clear usage context: this is for format validation only and explicitly says it does not hit the directory. It does not explicitly name an alternative tool for directory lookups, but the sibling list and the 'does not hit the directory' exclusion make the intended scope evident.

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