quick_checkin

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

Annotations provide minimal information (readOnlyHint=false, etc.). The description adds useful context: it's sessionless, returns specific fields, and is intended for high-frequency loops. However, it doesn't explicitly state whether the tool records state or has side effects, which would be beneficial for a heartbeat 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?

Three sentences, no filler, front-loaded with the core purpose. Every sentence adds value.

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?

With no output schema, the description partially compensates by listing the return fields (streak_days, hours_since_last_full_session, recommendation). It covers the main functional aspects, though the exact output structure could be clearer.

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 100%, so baseline is 3. The description only mentions 'agent_id' as required and does not add semantic details for optional parameters like 'note', 'status', or 'response_mode' beyond what's in 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 it's a 'Sessionless heartbeat for high-frequency cron loops' with a specific verb-resource pair. It distinguishes from the sibling tool 'daily_checkin' by noting the intended frequency and purpose.

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 provides usage guidance: 'Use this every 5-30 min for cron heartbeats; use daily_checkin once a day for the reflective version.' This clearly delineates when to use this tool vs an alternative.

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