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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false), so the description only needs to add context. It usefully discloses that the bubble is visible to nearby people and that empty input clears it, but says nothing about persistence, duration, or rate limits on repeated updates.

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?

Two short front-loaded sentences with zero filler; the primary purpose leads and the clearing behavior follows.

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 single-parameter, non-destructive social tool with no output schema, the description covers purpose, visibility behavior, and the clear-on-empty case. Only persistence semantics for the speech bubble are left unstated.

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 0%, so the description must carry the weight, and it does explain a non-obvious semantic: an empty text clears the bubble. It still omits any mention of the 72-character limit or what happens on overflow.

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 (sets) and resource (your speech bubble) plus the scope of visibility (people near you see it). It is clearly distinguishable from the object-editing siblings, though it never names or contrasts with any anonymous alternative.

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: the tool sets a bubble, and empty text clears it. There is no statement of when to use this versus other communication-adjacent tools, no prerequisites, and no exclusions.

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