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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so safety is covered. The description adds meaningful context beyond that: it discloses the per-request cost ($0.002) and enumerates the return payload (full text, author details, images, links, engagement metrics with reaction breakdowns). It does not cover auth or rate limits, but the added cost and return detail justify a 4.

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 short sentences are front-loaded: purpose, return payload, then billing. Each sentence adds distinct information and none is redundant, making it appropriately sized for the tool.

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 carries the return-value explanation and does so by listing the key fields an agent will receive. It also states the cost, so an agent can call the tool knowing the price and expected output. The only omission is sentiment behavior, but that is fully specified in the input 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%, so both url and get_sentiment are fully documented in the schema. The description adds only 'by URL,' which the schema already conveys, and says nothing about get_sentiment. Baseline 3 applies when 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?

The description names a specific verb and resource ('Get one LinkedIn post by URL') and scopes it to a single post, which differentiates it from sibling list/search tools like linkedin_person_posts and search_linkedin. It also enumerates the returned data, reinforcing what the tool is for.

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 purpose: use when you have a LinkedIn post URL and need full details. There is no explicit statement of when to choose this over search_linkedin or linkedin_person_posts, and no exclusions or prerequisites are given.

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