whisper

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

Discloses that messages from self to self are dropped, adding behavioral context beyond the annotations (readOnlyHint=false, etc.) which already indicate a write operation.

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 concise sentences: one stating purpose, one providing usage tips. No unnecessary words.

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 simple messaging tool with annotations and output schema, the description covers essential behavior (posting, CID discovery, self-drop). Complete enough for correct invocation.

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?

Though schema description coverage is 0%, the description explains to_cid via peers() and prefix matching, and 'content' is implied by context. This partially compensates but leaves content underspecified.

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?

Clearly states the tool posts a message visible only to a specific conversation, distinguishing it from broadcasting tools like broadcast or note.

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?

Explicitly instructs to use peers() to discover conversation IDs, explains prefix matching, and cautions that self-messages are dropped, providing clear when-to-use and how-to-prepare guidance.

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