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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description nonetheless adds genuinely new behavioral context: the credit cost model ('1 credit per result, minimum 1 per request') and that only public data is returned, which directly affects how an agent sizes the 'count' parameter.

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, front-loaded with purpose, then safety, then cost. Every sentence carries information the agent needs, and there is no redundant restatement of the title or schema.

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 should convey what a result looks like, but it only says 'returns public data' without indicating that the response is a paginated list of post objects with a nextCursor. The cost and safety context is complete, but the return shape is a gap for a tool with no output 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%, with all three parameters fully documented, including the cursor pagination contract and publicId format examples. The description adds nothing about parameter meaning beyond the schema, so the 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 states a specific verb and resource: 'List posts a LinkedIn member reacted to.' This is distinguishable from siblings like linkedin_get_posts_from_profile (authored posts) and linkedin_get_profile_comments (comments), though it does not explicitly name those alternatives. An agent can still infer the difference from the wording.

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 implied by the name and description but never stated: there is no explicit 'use this when you need reactions rather than authored posts or comments' guidance, and no mention of prerequisites such as whether the target profile must be public. Adequate for a simple lookup, but the routing logic against sibling tools is left to inference.

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