is_key_active

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

With no annotations, the description carries the full burden. It discloses that this is only a convenience check and that gateway enforcement is authoritative, which is a meaningful behavioral caveat. It implies a read-only operation ('Check'), but does not explicitly state side-effect freedom or error behavior, leaving a slight gap.

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 two sentences, front-loaded with the primary action, and every sentence adds value. It is concise and easy to scan, with no redundant wording.

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 simple two-parameter boolean check, the description covers the core function and a key caveat. However, it does not explicitly state the return type (though 'is_' implies boolean) or explain what 'currently authorized' means in terms of DID document semantics, which would improve completeness.

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 schema already provides 100% description coverage for both parameters, so the baseline is 3. The description mentions 'public key' and 'DID document' but adds no further semantic detail beyond what the schema already states.

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 uses a specific verb 'Check' and a clear resource: 'a public key is currently authorized for active operations in a DID document.' It clearly distinguishes this from sibling tools like rotate_key or verify_rotation_chain, which deal with key rotation rather than active authorization status.

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 phrase 'SDK convenience check; gateway enforcement is authoritative' provides clear context that this tool is a lightweight helper and not the final authority, advising against using it for enforcement decisions. However, it does not explicitly name an alternative tool or specify when-not-to-use, so it falls short of a 5.

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