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

Annotations already declare a safe read (readOnlyHint=true, destructiveHint=false, openWorldHint=false), yet the description adds non-obvious server-side behavior the annotations cannot express: matches are restricted to APPLIED, INTERVIEWING, and PROSPECTING status, so REJECTED/OFFER/withdrawn applications will not appear. It also discloses matching semantics (case-insensitive substring on both fields, which keeps two roles at one company distinct).

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?

Front-loaded with the core purpose and the call-order rule, then layered caveats, then outcome handling; the paragraph breaks map cleanly to decisions an agent must make. The standalone line 'Both `company` and `job` are required' restates the schema's required array and is the one sentence that does not fully earn 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?

An output schema exists, so return shape needs no explanation, and the description instead covers what the agent actually needs: when to call, what match semantics apply, which statuses are invisible to it, and what to do for each result. Nothing required to invoke this correctly or act on its result is missing.

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% and both parameters already document case-insensitive substring matching, so the baseline is 3. The description adds the conjunction semantics — both fields must match, and both are required — which is a real constraint beyond reading either property in isolation.

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?

States a specific verb and resource (checks whether a saved job application exists for a specific posting) and precisely scopes the operation to company + job title matching. It explicitly distinguishes itself from search_job_applications and create_job_application by naming both siblings and the gap each leaves.

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?

Gives an explicit call-order rule ('call this before create_job_application to avoid creating a duplicate') and branch instructions for both outcomes: if found is false, proceed to create; if true, prefer reusing the UUID via update_job_application or add_job_application_note. It also rules out search_job_applications with a concrete reason (it cannot filter by job title).

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