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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds behavior annotations cannot carry: that `state=active` can return multiple sprints due to parallel sprints or a disabled switch, and that the returned `version` is a required input for downstream mutation tools. It does not describe ordering or pagination, which keeps it below a 5.

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?

Four short sentences, front-loaded with the purpose, then the downstream contract, then the usage caveat. Nearly every sentence earns its place. The leading "List sprints." restates the title, which is a minor redundancy.

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?

With no output schema and no annotations covering return shape, the description carries that burden and does partially: it names the `version` field and warns about multiple results. It does not enumerate other returned fields (name, dates, state), so an agent still learns the record shape only by calling. Adequate but not fully complete.

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 50% — `project_key` is documented but the `state` enum values are bare. The description compensates by explaining the semantics of `state=active` (multiplicity, causes), which is the non-obvious value of that parameter. `planned` and `closed` are left unexplained and scope-limiting behavior of project_key is not addressed.

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 verb+resource ("List sprints") and immediately frames the result: each sprint carries its `version`. It distinguishes itself from siblings implicitly by naming what it feeds (update_sprint, close_sprint) rather than by contrasting with list_projects or get_burndown. Clear purpose, but sibling differentiation is indirect.

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 real routing guidance: tells the agent that starting a sprint is NOT a tool and instead the user presses Start sprint, so the agent should surface that to the user rather than look for a tool. It also warns to never assume a single active sprint. It does not say when to prefer list_sprints over get_burndown or list_projects, but for a list tool with an obvious scope that gap is minor.

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