send

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

With no annotations, the description fully reveals side effects: persistence, delivery behavior, agent validation, and return formats. It even names native mechanisms (hermes chat / codex exec / claude -p), giving a complete behavioral picture.

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?

The description is concise at three sentences, front-loaded with the core action, then followed by behavioral details and return format. Every sentence adds necessary value with no wasted 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?

Given no annotations and no output schema, the description covers validation rules, return values, persistence behavior, delivery mechanism, and error handling. It is fully sufficient for an agent to decide and invoke the tool correctly.

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?

The schema has no parameter descriptions (0% coverage), but the description compensates by explaining allowed agent names, the deliver flag's effect, and the response structure. The message parameter is self-evident, so all non-obvious parameters are well covered.

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 the specific action: 'Send a message from one agent to another.' It distinguishes itself from sibling ask_* tools by highlighting the durable mailbox persistence, making clear this is for persistent inter-agent messaging rather than one-off queries.

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?

The description provides clear context on when to use this tool: it always persists to a mailbox, and optionally delivers a one-shot notice. However, it does not explicitly mention alternatives or exclusions (e.g., when to use ask_claude instead), so it stops short of a 5.

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