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

Goes well beyond the readOnly/idempotent annotations: it discloses the required missions:read scope, the payload cost differential between views, the meaning of each pauseSource value, and where escalation details live (summary.escalation / escalationCause). It also chains behavior by telling the caller to pass proofRunSandboxId to list_artifacts.

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-loaded with the single-sentence purpose, then dense but purposeful detail. A few clauses (the enumeration of summary fields) are long but each carries information an agent would otherwise have to guess.

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?

With no output schema, the description carries the full burden of return-value explanation and does so thoroughly for both views, including nested field semantics and escalation reporting. An agent can call this correctly and interpret the response without further documentation.

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 baseline is 3, but the description adds real meaning: it enumerates what each view actually returns (summary fields vs full additions) and explains the downstream use of proofRunSandboxId. orgSlug and projectId narrowing are left to the schema.

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 and resource ("Fetch one mission") and immediately qualifies scope via the view modes. It does not, however, distinguish itself from the sibling inspect_mission, which plausibly reads the same resource, so an agent cannot fully disambiguate from the description alone.

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?

Explicitly frames the choice between view='summary' ("small enough to poll") and view='full' (adds stages, events, stats, outcomes), and routes two specific states to alternatives: resume_mission for checkpoint pauses and answer_qa_checkpoint for qa-unverifiable. It gives no guidance on when to prefer this over list_missions or inspect_mission.

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