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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true), so the description's real contribution is the failure mode: non-member ids are refused, and redundant add/remove operations are silent no-ops. Those are non-obvious behaviors an agent cannot infer from annotations. It omits permission requirements and what happens when the task does not exist.

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, each carrying distinct information: purpose, membership restriction, size cap, and no-op semantics. The purpose leads and every following sentence adds a constraint an agent needs. No filler or restatement of the title.

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 annotations handling idempotency and safety and an output schema handling return values, the description fills the remaining gaps: eligibility rules, batch limits, and no-op behavior. For a three-parameter mutation tool this is sufficient to call it correctly.

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 0%, and the schema's 'add'/'remove' items reference the task_id pattern, which is ambiguous about what those arrays actually hold. The description corrects this by specifying they take organization member ids and caps each side at 50. It adds no detail on task_id itself, but the schema pattern covers that.

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 first sentence states a specific verb pair and resource: 'Add and remove followers of a task in a shared project.' That is unambiguous and easily distinguished from nearby siblings like update_task or assign_conversation. It does not explicitly name a sibling it competes with, so it stops short of a 5.

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?

Usage context is implied by the scope constraint ('shared project', organization members only) rather than stated as when-to-use guidance. There is no explicit direction on when to use this versus update_task, which is the natural alternative for task modification. The membership and 50-per-side limits do effectively narrow how the tool should be called.

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