session_heartbeat

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

No annotations are provided, so the description carries the full burden. It mentions 'return the heartbeat status' but doesn't disclose what that status entails (e.g., success/failure, latency metrics), whether this is a read-only or state-changing operation, potential side effects (e.g., keeping a session alive), or any rate limits or authentication needs. For a tool with no annotation coverage, this leaves significant behavioral gaps.

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, efficient sentence that front-loads the core action ('Send a heartbeat') and purpose ('return the heartbeat status'). There's no wasted verbiage or redundancy, making it appropriately concise for a simple tool.

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 complexity of trading/venue management (implied by sibling tools), no annotations, and no output schema, the description is incomplete. It doesn't explain what a 'heartbeat' means in this context, what the returned status includes, or how this tool fits into broader session management workflows. For a tool with rich contextual signals but minimal disclosure, it should do more to compensate.

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 input schema has 100% description coverage, with the single parameter 'venue' documented as 'Venue name (e.g. NYSE, BATS, ARCA)'. The description adds no additional parameter semantics beyond what the schema provides, such as clarifying the format of venue names or how they relate to sessions. With high schema coverage, the baseline score of 3 is appropriate.

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 action ('Send a heartbeat') and the target resource ('for a specific venue session'), with a specific verb+resource combination. However, it doesn't differentiate this tool from its many siblings in the trading/venue management context, such as 'check_fix_sessions' or 'update_venue_status', which might involve similar session-related operations.

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 no guidance on when to use this tool versus alternatives. With 21 sibling tools including session-related ones like 'check_fix_sessions' and 'dump_session_state', there's no indication of when a heartbeat is appropriate versus other session checks or updates, nor any prerequisites or exclusions mentioned.

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