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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile of this lookup is fully covered. The description adds the useful detail of what the payload contains (quota, features, yearly discount), but says nothing about caching, freshness of pricing, or result size. With annotations carrying the behavioral burden, 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?

A single well-formed sentence with zero filler, front-loading the resource and then the fields returned. The parenthetical 'two months free' is the only embellishment and it conveys real pricing semantics.

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 no output schema, the description productively compensates by enumerating the returned fields (monthly price, yearly price, quota, features). The one remaining gap is the optional 'plan' filter, which the description ignores entirely, leaving the agent to discover filtering only from the schema.

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% — the single optional 'plan' parameter is documented in the schema with examples ('free', 'credits'). The description never references this filter, so it adds no meaning beyond the schema; baseline 3 applies.

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 names a specific verb+resource (list JobsPipe pricing plans) and enumerates exactly what each plan entry contains: monthly USD price, yearly price with two months free, monthly job quota, and included features. The sibling tools (list_job_sources, search_jobs) cover unrelated domains, so there is no plausible confusion to resolve.

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?

Usage is only implied by the resource itself — an agent infers it should call this when it needs pricing/plan information. There is no explicit when-to-use statement, no mention of the optional single-plan lookup as an alternative to listing everything, and no exclusions.

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