bus_heartbeat

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

With no annotations, the description carries the full burden; it does disclose the key side effect (marking the agent present) and what comes back (agent list with online status), which is meaningful. However, it says nothing about authentication expectations for the token, whether presence expires, or whether the call is idempotent or rate-limited.

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?

A single sentence that front-loads the operation and follows with the return value; there is no filler and nothing redundant.

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 two-parameter tool with no annotations and no output schema, the description partially compensates by stating the return shape, which is helpful given the missing output schema. The unexplained token parameter and absent lifetime/auth behavior for a presence-mutating call leave real gaps.

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% for two parameters, so the description must compensate. It only implicitly identifies 'agent' via 'this agent' and never mentions the token parameter at all, leaving a required credential's meaning and behavior undocumented in both the schema and the prose.

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 names a specific action ('mark this agent present') and a specific return ('get the live agent list with online status'), distinguishing it from pure lookups like bus_agents or bus_status. It does not explicitly say how it differs from those siblings, which keeps it from a 5.

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 heartbeat framing implies when to call it (periodic presence refresh), but there is no explicit statement of when to prefer it over bus_agents, bus_status, or bus_register, nor any exclusion or prerequisite. Usage must be inferred from the word 'Heartbeat'.

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