Get a credential's metadata

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

With no annotations, the description carries the full burden. It adds the important behavioral note that 'secrets are never returned', which is a safety-relevant trait. However, it doesn't disclose other behavioral aspects like whether it is a read-only operation (implied), error behavior, or idempotency, leaving gaps.

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 one short sentence (11 words) that is immediately informative. There is no wasted text, and the phrase 'secrets are never returned' adds crucial context without padding.

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?

This is a simple single-parameter fetch tool, and the description covers the core purpose and a key constraint (secrets are not returned). However, it does not specify what metadata fields are included or address error scenarios. Given the simplicity and presence of a clear 'metadata' term, the description is mostly adequate.

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 has zero description coverage for the single 'id' parameter. The description says 'by id', which clarifies that the parameter is the credential identifier, but it doesn't add further detail about format, required syntax, or what constitutes a valid ID. It provides minimal additional value beyond the parameter name.

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: 'Fetch one credential's metadata by id'. This specifies a distinct verb and resource, and the 'by id' scope differentiates it from listing all credentials or fetching a schema.

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 implies usage when a specific credential ID is known, but it does not explicitly mention when not to use this tool or suggest alternatives. Sibling tools like n8n_list_credentials exist, but this description doesn't provide direct comparison or exclusion guidance.

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