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

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'Create' implies a write operation, the description doesn't mention permission requirements, whether the credential is immediately usable, potential side effects, or error conditions. It adds minimal context beyond the basic action.

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 extremely concise with just two sentences that each serve a clear purpose: the first states the tool's function, the second provides essential usage guidance. There's no wasted language or redundancy, making it efficiently 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?

Given that there's an output schema (which handles return values) but no annotations and 0% schema description coverage, the description is incomplete. It provides good usage guidance but lacks parameter explanations and behavioral context needed for a creation tool. The presence of an output schema prevents this from being a complete failure, but significant gaps remain.

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%, meaning none of the three parameters (name, credential_type, data) have descriptions in the schema. The description doesn't explain what these parameters mean, what format 'data' should take, or what 'credential_type' refers to. It only mentions using another tool to discover required fields, which doesn't compensate for the lack of parameter semantics.

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 clearly states the action ('Create') and resource ('credential'), making the purpose immediately understandable. It distinguishes from sibling tools like 'update_credential' or 'delete_credential' by specifying creation rather than modification or deletion. However, it doesn't specify what type of credential or system context, which keeps it from being fully specific.

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 explicitly provides when-to-use guidance by stating 'Use get_credential_schema to discover required fields first.' This gives a clear prerequisite and alternative tool to use beforehand, helping the agent understand the proper sequence of operations.

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