find_contact

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

No annotations are provided, so the description carries full burden. It states the tool is 'Read-only,' which is a key behavioral trait. However, it does not disclose behavior on not found, error handling, or rate limits, which is acceptable for a simple lookup but minimal.

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 extremely concise with two sentences, front-loading the purpose and usage. No redundant information, 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?

Given the tool's simplicity (3 optional parameters, no output schema), the description is complete enough. It covers purpose, usage, and read-only nature. Could optionally mention behavior when no results, but not necessary for a lookup tool.

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 100% with each parameter already described. The description adds value by explaining the grouping constraint: 'Provide either an email or a reference_source + reference_id.' This clarifies mutual exclusivity beyond the schema's individual descriptions.

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 'Find a single contact by email, or by reference source + id.' It specifies the verb 'find' and the resource 'contact,' and distinguishes itself from sibling tools like 'search_contacts' (which likely returns multiple) and 'get_contact_notes' (different resource).

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 clear guidance: 'Provide either an email or a reference_source + reference_id.' It states that the tool is read-only, implying no side effects. However, it does not explicitly compare with alternatives or mention when not to use it, which would earn a 5.

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