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

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower. The description adds genuinely useful behavioral context beyond them: the description text is only an excerpt 'when the source provides one' and 'the listing URL has the complete text', warning the agent that the returned body may be truncated.

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?

One dense but well-ordered sentence front-loads the return shape, then closes with a single short caveat about full text. No filler sentences; every clause 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?

With an output schema present, the description needn't document return values, and it still flags the one thing an agent must know (the excerpt may be partial). Input, provenance, and output caveat are all covered for a single-parameter read 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%, and the description's id provenance (search_jobs id or jobs.uxjobs.io slug) largely restates what the schema already documents. Baseline 3 is appropriate since the schema does the heavy lifting.

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 (Return) and resource (one job listing in detail), then enumerates the actual payload (location, workplace, posted salary, apply link, description excerpt). It is immediately distinguishable from sibling search_jobs because it fetches a single listing by id rather than searching.

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?

Explicitly tells the agent where the id comes from — 'the id returned from search_jobs (or the jobs.uxjobs.io page slug)' — which sets up the search-then-fetch workflow. It stops short of naming an exclusion or stating when not to use this tool (e.g. when only a summary is needed).

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