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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds context about the return content (full contact and deals), which is beyond the schema. However, it does not disclose any additional behavior such as error conditions, authentication needs, or limitations. Given the annotations, the added value is moderate but not extensive.

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 sentence that front-loads the primary purpose (one contact in full) and then adds the deals detail. No filler or redundancy. It is concise and every word earns its place.

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?

For a tool with one parameter, no output schema, and annotations covering safety, the description sufficiently communicates what is returned. It does not specify behavior when no deals exist or error scenarios, but these are minor given the simplicity and the annotations. The description is adequate for an agent to call it correctly.

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 input schema has 100% description coverage for the single parameter contactId, with explicit instructions about using an exact ID from a read tool. The tool description adds no additional semantic meaning about parameters. Since the schema covers all semantics, a 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 clearly states the tool retrieves a single contact in full, including associated deals with specific fields (stage, property, offer). This distinguishes it from siblings like list_contacts (which lists many) and get_deal (which focuses on deals). The verb is implicit but the resource and scope are precise.

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 context implies use when a full single contact is needed, but no explicit guidance on when not to use it or alternatives is provided. The description does not mention that this is for a known contactId or that it should be used over list_contacts when only one contact is required. The usage is implied rather than stated.

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