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

With `readOnlyHint: false` already signaling a mutation, the description adds genuinely useful behavioral context: the sprint is created in a 'planned' state and requires a separate `start_sprint` call to become active. This goes beyond the structured annotations and shapes agent expectations about lifecycle. It doesn't describe e.g. idempotency or duplicate policy, but that's a minor gap for this operation.

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 trigger, and every sentence earns its place: the first gives the trigger, the second disambiguates the state and sibling, the third guards against synonym ambiguity. 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?

The core workflow (`create` → `planned` state → later `start_sprint`) is clearly described, and the parameter names are mostly self-explanatory; but there is a clear gap in parameter guidance and no mention of output or defaults, despite the schema providing no descriptions. Adequate for a simple tool, but not fully complete enough for all agent calls.

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?

The schema description coverage is 0%, so the description must compensate for the four parameters (`name`, `goal`, `startsAt`, `endsAt`). It does not. The phrase 'plan a new sprint (e.g. 'start a sprint for next week')' only hints at date-related parameters and never explains `goal`, `name`, or the meaning or format of the time boundaries. Some parameters are inferable from their names, so this is not a bottom-score 1, but the description clearly leaves the parameter pain of the weight.

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 verb ('creates') and resource (`sprint`), and distinguishes itself from the sibling `start_sprint` by saying sprints are created in 'planned' state. The synonym guidance (focus, cycle, iteration, week) further disambiguates the resource. This is clear, specific, and differentiates from the most likely sibling.

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?

Gives an explicit trigger ('when the user wants to plan a new sprint'), and tells the agent when NOT to treat this as starting a sprint ('call start_sprint separately when ready to begin tracking'). This is a direct when/when-not with the relevant alternative, so an agent can route correctly without guessing.

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