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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds value by disclosing the return scope (enriched fields, activity history, campaign membership), which is helpful given no output schema. However, it doesn't discuss potential errors or response format.

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, information-dense sentence with no redundant phrases. It front-loads the core action and includes compound object details efficiently.

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 simple read-only tool with two optional parameters and no output schema, the description covers the key invocation aspects (what it returns, how to specify the contact) reasonably well. It lacks explicit usage guidance among siblings, but the simplicity of the tool reduces the need for more.

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%, so the description must compensate. It identifies 'email' and 'contact ID' as the two lookup parameters, but it doesn't clarify whether they are mutually exclusive or if both are accepted together. This adds partial meaning beyond the bare schema names.

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 ('Get full details of a single contact') and specifies the resource ('contact') and the lookup keys ('email or contact ID'). It distinguishes this from sibling search/list tools by focusing on single-contact retrieval with enriched fields, activity history, and campaign membership.

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 you have a specific contact identifier and need a complete record. It doesn't explicitly mention alternatives or exclusions, but the context is clear enough that it's for single-contact lookups rather than bulk operations.

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