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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is known. The description adds substantive context beyond that: the operation is irreversible and non-resumable, the user must create a new request, and only pending (not completed) requests qualify. It doesn't cover auth/permission requirements, which keeps it just below a 5.

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?

Front-loads the verb and the three request sources, then layers constraints and the use case, so the critical routing information appears first. It is slightly dense with em-dash clauses but every sentence carries information.

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 destructive mutation with no output schema and no annotations covering reversibility, the description supplies the missing essentials: what is being destroyed, that it is final, preconditions, and the triggering user intent. The unexplained projectId parameter is the main remaining gap.

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%, so the description must carry the full explanatory burden. It hints that jobId originates from screenshot_preview ('jobId from that tool'), but that parenthetical is ambiguous for the credential/custom-domain cases, and projectId is never explained at all. Half the parameters remain undocumented in both schema and description.

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?

States a specific verb (withdraw/cancel) and resource (a pending request), and enumerates exactly the three request sources it operates on — request_external_resource, publish_app, screenshot_preview — naming sibling tools directly. An agent can distinguish this from other mutation tools without opening the schema.

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?

Gives clear context for use ('when the user says to stop or they don't want to proceed') and preconditions ('only pending requests can be cancelled'). It stops short of naming alternate tools for genuinely different situations, but the operation is narrow enough that this is minor.

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