mark_todo_done

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

Beyond the `openWorldHint` annotation, the description discloses that the call mutates remote GitLab state, requires project or group permissions, and surfaces GitLab's error semantics (validation, conflict, permission, rate-limit) rather than silently succeeding. This is useful behavior context consistent with the annotation — no contradiction.

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 dominated by generic template language that could be pasted into any tool — the `project_id`/`group_id` guidance is actively misleading since this tool takes only an `id`. The useful content ('Mark a GitLab to-do item as done' plus the side-effect sentence) could fit in two concise sentences.

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 tool with a single parameter and no output schema, the description covers the key aspects an agent needs: the operation, the side effects, permission requirements, and error behavior. The only deduction is for the presence of irrelevant boilerplate that slightly muddies otherwise adequate coverage.

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 100% and the description adds nothing about the single `id` parameter beyond what the schema already provides. In fact, the sentence about `project_id` or `group_id` references parameters that do not exist in this tool's schema, which is confusing even if intended as generic template text. The baseline of 3 for fully covered schema is correct here.

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?

'Mark a GitLab to-do item as done' is a specific verb + resource phrase that unambiguously states the core function. However, the description does nothing to distinguish this from sibling `mark_all_todos_done`, and the generic sentence 'choose a sibling tool when you need a different resource or lifecycle action' reads as boilerplate rather than targeted differentiation.

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 instruction to 'choose a sibling tool when you need a different resource or lifecycle action' is tautological — it provides no actionable decision boundary. For example, it never tells the agent when to prefer `mark_all_todos_done` over this tool. No specific alternatives, exclusions, or conditions are given.

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