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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true), and the description adds material facts those annotations cannot express: the plaintext apiKey is returned exactly once and never again, and identical requests are deduplicated for 24 hours. Both are consequential, non-obvious behaviors an agent must know before calling.

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?

Three tight sentences, each carrying a distinct fact (action, scope semantics, secret-once plus dedup). The "Step 11: Manage API keys." prefix is slightly noisy but does situate the tool in a workflow.

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?

With no output schema, the description still tells the agent that the plaintext key appears in the result, which is the critical return-value fact. For a 4-parameter, zero-required mutation tool it is close to complete, missing only permission prerequisites and the rest of the response shape.

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 coverage is 50%, with name and scope undocumented in the schema; the description compensates by defining what manage and read actually authorize. It also reinforces the idempotencyKey contract (reuse on retry, new value to deliberately repeat), leaving only the name parameter unaddressed.

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 gives a specific verb and resource ("Create an API key") and immediately qualifies the two modes it can be created in. It is clearly distinct from the list/revoke siblings by naming the creation action, though it never names those siblings explicitly.

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?

It gives real decision guidance on the scope choice (manage acts as owner vs read for read-only/GET-only) and on when to reuse versus replace an idempotencyKey. It says nothing about when to use this tool versus ringkit_list_api_keys or ringkit_revoke_api_key, so tool-selection guidance is only implied by the name.

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