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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds scoping context ('of the company'), implying the company_id parameter filters results. However, it doesn't disclose any other behavior such as pagination, sorting, or the structure of the response. Since annotations carry the main behavioral burden, a 3 is appropriate.

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, direct sentence with no redundancy. It front-loads the action and resource, making it immediately scannable. 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 simple read-only list with one parameter and no output schema, the description is adequate but minimal. It lacks definition of what constitutes a 'candidate source' and doesn't mention any filtering or return details. However, given the low complexity and annotation coverage, it meets the minimum viable threshold.

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% and the description does not explicitly explain the company_id parameter. The phrase 'of the company' hints at its role but doesn't clarify requiredness or formatting. For a single-parameter tool, the description should more explicitly state how the parameter is used; this gap lowers the score.

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 the specific verb 'List' and resource 'candidate sources,' clearly indicating a read operation. It distinguishes itself from other list tools by targeting a unique resource type, though it doesn't explicitly differentiate from siblings like hires_list_candidates or hires_list_origins. The meaning is clear enough for an agent to identify the tool's purpose.

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?

No guidance is provided on when to use this tool versus other list tools. With over a hundred sibling tools, an agent would need to infer that this is for retrieving candidate sources specifically, but there is no explicit context or exclusion of alternatives. The description offers no situational advice.

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