cronometer-mcp

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 states 'Add a biometric entry', implying a write operation, but does not disclose behavioral traits such as authentication requirements, rate limits, idempotency, or what happens on duplicate entries. The description adds minimal context beyond the basic action, leaving gaps in transparency.

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 appropriately sized and front-loaded, starting with the core purpose and supported types, followed by a structured 'Args' section. Every sentence adds value, with no wasted words. It could be slightly more concise by integrating the args list more seamlessly, but overall it is efficient and well-structured.

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, 0% schema description coverage, and an output schema present, the description is moderately complete. It fully explains parameters but lacks behavioral details (e.g., auth, errors). The output schema reduces the need to describe return values, but for a write tool with no annotations, more context on side effects or constraints 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?

Schema description coverage is 0%, so the description must compensate. It adds significant meaning beyond the schema by listing supported metric types with units (e.g., 'weight (lbs)'), specifying allowed values for 'metric_type', explaining 'value' units, and detailing the 'entry_date' format ('YYYY-MM-DD'). This fully documents all three parameters, compensating for the lack of schema descriptions.

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 specific action ('Add a biometric entry') and resource ('to Cronometer'), and distinguishes it from sibling tools like 'remove_biometric' or 'get_recent_biometrics' by focusing on creation rather than retrieval or deletion. It specifies the supported metric types, making the purpose explicit and differentiated.

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. It does not mention prerequisites (e.g., authentication), exclusions, or comparisons to sibling tools like 'add_food_entry' or 'remove_biometric'. Usage is implied by the action but lacks explicit context or alternatives.

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