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

Annotations only declare non-readonly, non-idempotent, non-destructive. The description adds substantive behavior: the wording becomes locked after approval and further variation is refused until a revision suggestion is accepted. That lock-in/refusal behavior is not derivable from annotations and is exactly the context an agent needs.

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 core action, then the lock constraint, then the boundary on scope. No filler; slightly dense but every clause carries meaning.

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?

An output schema exists, so return values need not be described. The description covers the mutation's lifecycle constraint and the fact-source boundary, which are the main ambiguities for a 2-param write tool. Minor gap: no mention of what happens on rejection or validation failure.

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 0% for two required params (milestoneSetId uuid, wording string 1-2000 chars), so the description must compensate. It conveys what 'wording' semantically represents but adds no format, scope, or length guidance and says nothing about milestoneSetId. It partially compensates, not fully.

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 ('Record') and resource (client-facing wording about milestones, completion, payment release), which is distinguishable from siblings like define_milestone or approve_milestones. It does not explicitly name a sibling it replaces, but the resource is narrow enough for an agent to route correctly.

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 a concrete precondition/constraint: after approval, differing wording is refused until an accepted revise_client_wording suggestion, and the assistant must not exceed this wording plus facts from read_milestone_set. It does not cover all alternatives among the 15 siblings, but the when-not condition is explicit.

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