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

With no annotations provided, the description carries full burden. It usefully discloses that secrets are never exposed (a key security constraint) and specifies 'metadata only' output. However, it doesn't mention pagination behavior, rate limits, authentication requirements, or what specific metadata fields are returned, leaving gaps in behavioral understanding.

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 a single, efficient sentence that front-loads the core purpose ('List all credentials') and immediately adds crucial behavioral context ('metadata only — secrets are never exposed'). Every word earns its place with zero wasted text.

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 the tool's simplicity (one optional parameter, read-only operation), the presence of an output schema, and no annotations, the description is reasonably complete. It covers the key security constraint about secrets and specifies metadata-only returns. For a basic list operation, this provides adequate context, though additional behavioral details would enhance 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 description adds no parameter information beyond what's in the schema (which has 0% description coverage for the single 'limit' parameter). However, with only one optional parameter and an output schema present, the description adequately compensates by focusing on output behavior. The baseline would be 3 for high schema coverage, but with 0% coverage and minimal parameters, a 4 is appropriate as the description provides sufficient context for tool selection.

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 verb ('List') and resource ('credentials') with a specific scope ('all'). It distinguishes from siblings like 'get_credential_schema' by focusing on listing metadata rather than schema details. However, it doesn't explicitly differentiate from other list tools like 'list_data_tables' or 'list_workflows' beyond the resource type.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, timing considerations, or comparisons to other credential-related tools like 'create_credential' or 'update_credential'. The agent must infer usage from the tool name alone.

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