search_candidates_by_email

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

With no annotations, the description discloses the read-only nature and states it 'Returns the candidate record directly'. It does not cover edge cases like no matches, but the core behaviors are transparent beyond the annotation absence.

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 concise sentences, front-loaded with the main action, and no extraneous detail. Every sentence adds value.

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 simplicity (one required parameter), the presence of an output schema, and the explicit usage alternative, the description is complete for an agent to select and invoke 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?

Schema coverage is 100%, so the parameter description already provides meaning. The description reinforces the 'exact' nature of the email but does not add significant new semantics beyond the schema.

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 'Look up a candidate by exact email address' with a specific verb and resource, and explicitly distinguishes itself from the sibling tool 'search_candidates_by_name' by targeting email-based lookup.

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?

It explicitly states when to use this tool ('Use when the user provides an email instead of a name') and names the alternative for name-based lookup, providing clear contextual guidance.

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