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

Beyond the annotations, it discloses idempotent MERGE semantics ('only the fields you send are updated, existing fields survive'), value range-checking to prevent typos from poisoning baselines, and the rule that confounders should be ticked rather than folded into numbers. These are non-obvious behaviors that materially affect how an agent should construct calls.

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 long but dense, with every sentence earning its place. The most important behavior — daily-readiness MERGE-upsert idempotency — is front-loaded, and supporting detail on batch backfill and field interpretation is organized logically without redundancy.

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 complex write tool with many optional fields and no output schema, the description covers idempotency, field groups, ranges, batch limits, and the confounder-handling rule. An agent has enough information to construct valid calls and make correct decisions about which values belong where.

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?

With 0% schema description coverage, the description fully compensates by explaining the semantic groups inside items: the subjective McLean 1-5 core, optional wearable-derived objective fields, and confounder flags. It also highlights batch size (up to 90) and gives example ranges, adding substantial meaning beyond the raw property names.

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 opens with a specific action and resource: 'Record the athlete's daily readiness'. It adds decisive behavioral detail — 'one entry per date, idempotent MERGE-upsert' — and clearly distinguishes the tool from read-side siblings like get_readiness and get_readiness_today.

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 the primary use case (daily readiness logging) and explicitly mentions a batch backfill scenario from exported HRV/RHR/sleep data. It does not explicitly name excluded alternatives or contrast with log_metric/log_session_rpe, but the readiness-specific framing makes selection unambiguous in most contexts.

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