create_milestone

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

With no annotations provided, the description must disclose side effects, but it does not. It states the rule 'Exactly one milestone should be active at a time' but doesn't clarify whether the tool enforces this or merely advises the user, nor what happens to an existing active milestone when a new one is created.

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?

The description is two sentences with a clear verb-adverb-noun structure and no filler. The key constraint is front-loaded after the action, making it easy to scan.

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 description covers purpose and usage, but given the 'exactly one active' rule, it doesn't explain the operational behavior (e.g., auto-deactivation, validation). Since there is no output schema or annotations, these gaps make the tool slightly ambiguous for an agent.

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 covers all three parameters with descriptions, so the baseline is 3. The description adds context by explaining milestones are coarse phases of 2-6 stages, which helps interpret the name parameter, but it doesn't add new details about status or description beyond the schema.

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 'Start a new coarse project phase (timeline)', which clearly identifies the action and resource. The word 'coarse' distinguishes it from task-level tools like create_task, and the example 'Phase 1: Core Implementation' reinforces the intended scope.

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 description explicitly says 'Use for 2–6 big stages', providing a concrete sizing guideline. It stops short of naming alternatives or specifying when not to use it, but the coarse-vs-fine distinction is implied by 'coarse project phase' versus sibling tools like create_task.

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