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

Annotations already declare destructiveHint=true, openWorldHint=true, and readOnlyHint=false, but the description adds rich context beyond them: the 60-minute edit window, the message-type restriction, that the other person sees the new text, and a 100/day daily allowance. These are exactly the behavioral traits an agent needs to invoke it safely.

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 Ids in/Ids out convention, then the core operation and its constraints in tight sentences with no filler. The bracketed Ids preamble is slightly meta but carries genuine wiring value for the agent.

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?

For a mutation tool with no output schema, the description covers operation, editability window, message-type constraint, visibility side effect, and rate limit. Nothing an agent needs to call it correctly 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 description coverage is 100%, so the baseline is 3, and the description lifts it by supplying provenance for messageId ('from list_chat_messages → messages[].id'), an explicit Ids in/Ids out convention, and confirming text is the replacement content. The connectionId parameter is not elaborated in the description, keeping it short of a 5.

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 ('Change the text') and resource ('ONE message you sent on LinkedIn'), with explicit scope ('ONE'). This cleanly distinguishes it from siblings like send_message, delete_message, and react_to_message without needing to open any schema.

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 strong applicability conditions: only within 60 minutes of sending and only for ordinary (not Sales Navigator or Recruiter) messages. It does not, however, name alternative tools for the cases it excludes (e.g. editing a Recruiter message), leaving the agent to infer the fallback.

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