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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile, and the description adds genuine extra context: the default lookback/lookahead window and the fact that empty days are surfaced. It still omits pagination or ordering behavior, but it meaningfully supplements the annotations.

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?

A single compact sentence that front-loads the resource and packs scope, contents, defaults, and the empty-day detail with no filler.

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 zero-required-parameter read tool with no output schema, the description adequately conveys what comes back (planned workouts and to-dos per day plus empty days). It could say more about return shape or ordering, but nothing critical is missing.

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% — both days_back and days_ahead already carry 'Default 7/14, max 60' descriptions. The description only restates those defaults, adding no semantics beyond the schema, so the baseline of 3 applies.

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?

States a specific resource ('the user's training calendar') and its contents ('planned workouts and to-dos per day'), plus the default time window. It is clearly distinguishable in content from history-oriented siblings like get_workout_history, but it does not explicitly contrast itself with them.

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 default window and the mention of empty days imply the scenario (looking at the current planning horizon), but there is no explicit when-to-use guidance and no named alternative among the many get_* siblings. Usage is inferable rather than stated.

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