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

Beyond the annotations (readOnlyHint=false, destructiveHint=false), the description adds little behavioral context. It simply restates the operation without mentioning side effects, reversibility, permissions, or what happens if the deal is already won. The 'set close date' part is already covered by the parameter schema, so no meaningful extra transparency is provided.

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 a single, compact sentence that conveys the essential action. It is well-structured and directly states the purpose, with no redundant words or fluff.

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 tool is simple, and the schema/annotations cover parameters and safety cues. However, the description lacks context about usage relative to closely related tools (e.g., mark_deal_lost) and any prerequisites or consequences of the action. It is enough for basic invocation but not fully complete for nuanced real-world decisions.

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% with clear descriptions for both parameters. The tool description mentions 'set close date', which reinforces the closingDate parameter, but adds no new meaning beyond what the schema already provides. The description neither clarifies formats nor prerequisites, so it stays at the baseline.

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 clearly states the tool's purpose: 'Mark a CRM deal as won and set close date.' This uses a specific verb and resource, and distinguishes it from sibling tools like mark_deal_lost by explicitly noting the 'won' outcome and the additional action of setting a close date.

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 implies usage (you use this to mark a deal won) but provides no explicit guidance about when to use this versus alternatives like mark_deal_lost or update_deal_stage. There are no stated exclusions or alternative recommendations, so guidance is only implicit.

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