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

Annotations already declare destructiveHint=false and readOnlyHint=false, so the agent knows this is a non-destructive mutation. The description adds genuinely new behavioral context: it is a private, per-user filter ('a filter for them only - nobody is told no'), which is not conveyed by any annotation.

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 short sentences front-load the effect, and the privacy clarification follows immediately. The trailing docs URL is useful and cheap. The phrasing is slightly informal but not padded.

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 single-parameter mutation with a full annotation profile and no output schema, the description covers effect, scope, and privacy adequately. The only gap is how to obtain a valid openMissionId, which the docs link partially addresses.

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?

There is one required parameter (openMissionId) with 0% schema description coverage. The description's reference to 'an open mission suggested to them' implicitly ties the parameter to that mission, but it adds no format, source, or retrieval guidance beyond the schema's type.

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 concretely states the effect: a suggested open mission stops being suggested to the person. It is a distinct operation from siblings like findMissionTool or listMyWishOffersTool. It stops short of using a crisp verb+resource phrasing, describing the outcome narratively instead.

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 implies the trigger condition ('the person says an open mission suggested to them is not relevant'), which gives usable context. However, it names no alternative tools or when-not-to-use guidance, so an agent must infer how this differs from related actions such as finding or applying to missions.

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