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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds genuine behavioral context beyond that: the metric-enabled filtering rule, the default-all-metrics behavior, the computed first-to-last change, and the Cotlet API key auth requirement with app-level access.

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 first two sentences are redundant, repeating 'date, time and unit' (and again 'date, time, value and unit') for the same return shape. Front-loading is fine, but the duplication wastes space without adding 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?

For a read-only, single-resource query tool with no output schema, the description adequately covers what is returned (entries plus range change), the filtering behavior, and auth needs. Return shape is explained, which compensates for the absent output schema.

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 coverage is 100%, so the schema already documents from/to/metric/client_id and their defaults. The description largely restates the metric default already in the schema; its only incremental addition is the 'metrics enabled for that client' rule. Baseline 3 is appropriate when the schema carries the parameter detail.

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 gives a specific verb and resource: it returns a client's tracked body-metric entries (weight, custom metrics) with date, time, value, unit, and range change. This clearly separates it from the write-side sibling everfit_log_body_metric, though it never names that sibling explicitly.

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?

It states useful conditional behavior ('Only metrics enabled for that client return data' and 'Without metric, it returns every tracked metric'), which is implied usage context. However, it gives no explicit when-to-use guidance or mention of alternatives like everfit_get_client or everfit_log_body_metric, leaving the agent to infer routing.

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