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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value by stating 'Read-only and spends no quota' and specifying the required auth scope ('signatures:read') and behavior without a key ('returns dashboard setup instructions'). No contradiction with annotations.

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 sentences, each serving a distinct purpose: (1) stating what the tool does and its unique value, (2) listing use cases, (3) noting behavioral/property traits. No redundancy or filler. Front-loaded with the core action.

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 has only one parameter, no output schema, and annotations cover safety, the description adequately covers purpose, use cases, and auth. It hints at the return structure ('placed_fields array and position'). While it could more explicitly describe the full response object, the description is sufficient for a simple fetch operation.

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 100% (the single parameter has a description: 'ID from list_signature_templates.'). The description does not provide additional details about the parameter beyond what the schema already offers, so the baseline score of 3 is appropriate.

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 ('Fetch') and clearly identifies the resource ('one e-signature preset in full'). It explicitly distinguishes from the sibling tool list_signature_templates by noting that list_signature_templates omits the placed_fields array and position. This provides strong differentiation.

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 concrete use cases: inspect or copy field layout before applying via create_signature_request, or as starting point for preview_field_placement. It also notes read-only and no quota, which implies appropriate contexts. However, it does not explicitly state when NOT to use this tool or name alternatives beyond the implicit ones.

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