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

Annotations already declare read-only, idempotent, non-destructive, and closed-world behavior, so the baseline is covered. The description adds meaningful behavioral detail beyond annotations: the 90-day default window, the three metric options with their defaults, and the fallback behavior when an unknown exercise slug is provided (returns candidates, logged ones first).

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, front-loaded with the usage condition, then return granularity, date defaults, metric semantics, and error handling. No redundant or filler content.

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 progression query with rich annotations and an output schema, the description covers the remaining gaps: default date window, metric meanings, and unknown-slug fallback. An agent has everything needed to invoke it correctly.

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: it explains exercise_slug, specifies that from/to default to the last 90 days, and lists metric values and defaults (max_weight default, estimated_1rm as Epley, volume). All four parameters are given semantic context beyond their bare types and enum.

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 states a specific verb and resource: it returns one point per training day tracking an exercise's progression over time. It also includes a concrete user-query example, making the purpose immediately clear and distinguishable from sibling tools like get_personal_records or get_stats_overview.

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 gives a clear trigger condition: 'Use this when the user asks how one exercise has progressed over time.' However, it does not name alternatives or state when not to use this tool, so the routing guidance is clear but not exhaustive.

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