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

The description discloses a key behavioral constraint not fully captured by annotations: only one sprint can be active, and the tool fails and names the active sprint if one is already running. It does not spell out the state change ('active sprint' becomes this one), but the failure mode is enough to prepare an agent. No contradiction with readOnlyHint=false, destructiveHint=false, or openWorldHint=false.

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?

Two sentences and every sentence earns its place: the first states the triggering condition, the second states the constraint and recovery path. The most important usage condition is front-loaded, and there is no filler or repetition.

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 single-parameter mutation tool with no output schema, the description provides the essential use case, the active-sprint constraint, and the retry path. It could be stronger by explicitly identifying the id parameter as the target sprint and pointing to list_sprints or get_active_sprint, but these are minor gaps, not critical omissions.

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 only parameter, id, has no schema description and the description does not explicitly define what id refers to. It is contextually implied that id is the sprint to start, but the description never directly says this. With 0% schema coverage, the description should compensate, and it does not.

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 ('begin a previously planned sprint') and clearly distinguishes this from related siblings like create_sprint and complete_sprint. The one-active-sprint rule and the explicit mention of complete_sprint further remove ambiguity about what this tool does and does not do.

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 exactly when to use the tool: when the user is ready to start a previously planned sprint. It also gives a concrete exclusion and recovery path: if another sprint is active, complete it via complete_sprint, then retry. This is explicit, actionable guidance with no need for inference.

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