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

Annotations already declare non-readOnly and openWorld, but the description adds real value beyond them: it reaches other people, requires per-call user confirmation by default, and requires a Cotlet API key scoped to this app. It stops short of 5 because it doesn't say what happens to the activity record afterward or whether the action is reversible.

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 first two sentences are largely redundant ('Mark an activity as completed, with an activity result' vs 'Marks one activity as completed and records one of your activity results'), and the 'MarketSharp:' prefix duplicates the title. Information is front-loaded, but a sentence could be cut.

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 2-param mutation with annotations covering the safety profile and no output schema, the description covers confirmation, auth, and external reach, which is most of what an agent needs. It leaves the meaning/values of 'activity result' unstated but the schema carries that.

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%, so the schema already documents both activity_id and result. The description restates that 'result' is one of your activity results but adds no format, allowed values, or syntax beyond the schema; baseline 3 applies.

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 states a specific verb+resource ('Mark an activity as completed') and clarifies that it also records an activity result, which distinguishes it from marketsharp_add_activity and marketsharp_list_activities. It does not explicitly name which sibling to prefer for appointment results, 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?

It gives operational guidance ('confirm each call', 'you can switch that off') but never states when to choose this tool over alternatives like add_activity or result_appointment. The when-to-use is only implied by the tool's function.

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