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

With no annotations provided, the description carries the full transparency burden. It discloses that the engine runs progression logic (double-progression, e1RM), detects PRs, returns per-exercise outcomes, and provides next-time targets, plus kg units. This is substantial and goes beyond a simple 'log' statement.

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 concise sentences: the first is the core purpose, the second explains the engine behavior and outputs, and the third clarifies units. Every sentence adds value and the main action is front-loaded.

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 moderately complex logging tool with no output schema, the description explains the key return data (per-exercise outcomes) and behavior (progression, PR detection). It omits semantic details about goal/dayIndex and any edge cases, but covers what an agent needs to make the call and understand the response.

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 only 33%, so the description must compensate. It adds important meaning: 'Weights are in kg' and 'completed sets' for the exercises array. However, it does not clarify goal or dayIndex semantics, leaving those under-specified. The schema provides enum/integer types but no real-world meaning.

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 opening phrase 'Record what the athlete actually lifted' gives a specific verb and resource, making it clear this is a write operation for logging completed workout sets. It distinguishes itself from read-oriented siblings like get_todays_session and get_program by focusing on recording actual performance.

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 clearly implies when to use it: after the athlete finishes lifting, to log what was actually completed. It does not explicitly name alternatives or exclusions, but the context is unambiguous enough for an agent to select this tool over read/session tools.

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