agent_heartbeat

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the action without explaining side effects (e.g., what happens when marked offline, whether it resets a timer, or any authentication requirements). The behavior is not fully transparent for a session-management tool.

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 a single, concise sentence that is front-loaded with the primary action. Every word earns its place, with no redundant or extraneous information.

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 the simplicity of the tool (one parameter, output schema present), the description is mostly sufficient. However, it lacks context about when to send heartbeats (e.g., periodic refresh) and the implications of going offline. The presence of an output schema reduces the need to describe return values, but a bit more on session behavior would improve completeness.

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 one parameter 'status' with an enum and a default, but no descriptions. The description partially compensates by mentioning 'presence' and 'offline', which map to the enum values. However, it does not clarify the default value or explicitly enumerate the allowed values, leaving the agent to infer from the schema.

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 clearly states the tool's function: refreshing presence or marking offline. It uses specific verbs and identifies the resource (authenticated session's presence), which distinguishes it from sibling tools that handle profiles, messaging, or rooms.

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 implies usage: it's for updating presence status on an authenticated session. However, it provides no explicit guidance on when to use it versus alternatives, nor does it mention any exclusions or specific scenarios like periodic heartbeats. This is acceptable but not fully explicit.

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