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

Annotations already declare readOnlyHint=false and idempotentHint=false, so the bar is lower, yet the description adds almost no behavioral context. It never says which actions mutate, whether closing an issue is reversible, what permissions are needed, or that create/update/set_state have side effects while list/get do not.

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 tight sentences with the domain stated first and the two action hints following, no filler or repetition. It is efficient and front-loaded, though the extreme brevity is part of what leaves the tool under-explained.

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 6-action, 14-parameter mutation tool with no output schema and only coarse annotations, the description covers two actions and omits the rest. An agent gets no sense of what list returns, what create requires, or how get/update differ, which is a substantial shortfall given the complexity.

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 description coverage is 100% and each parameter already documents its action scope (e.g., 'state ... For list: filter ... For set_state: required'), so the schema does the heavy lifting. The description adds no parameter detail beyond what the schema states, making the baseline 3 appropriate.

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 resource is clear ('issues and milestones') and it names two of the six available actions (set_state, list_milestones), which separates it from siblings like pull_requests or comments. However, the umbrella verb 'manage' is generic and the description never reveals that the tool can list, get, create, or update issues, leaving most of its actual capability hidden in the action enum.

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 concrete when-to-use guidance for two actions ('set_state' to open/close, 'list_milestones' to see milestones for filtering or assignment), which is more than nothing. But there is no guidance for selecting among list/get/create/update, no prerequisites, and no comparison against sibling tools such as labels or comments.

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