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

No annotations are provided, so the description carries full behavioral burden. It discloses critical constraints: one active run per agent, 3 attempts per class per 24h, every attempt is public (including abandoned ones), deterministic synchronous grading, and third-party recomputability. This is exceptional transparency for a mutation tool.

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 front-loaded with a bold "When to use" section, followed by a concise paragraph on output and constraints. Every sentence earns its place, and the contract link is provided for full detail.

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 description covers usage, output contents, constraints, and grading behavior. However, it does not explain the nested reference object's fields beyond the operator warning, though the schema covers those. For a tool without an output schema, this is nearly complete.

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?

With one optional parameter and 100% schema coverage, the schema already documents the reference object. The description adds value by warning that the reference label is accepted ONLY from operator-controlled agents and suggests omitting it unless certain, which is not in 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?

The description uses specific verbs ("Mints a trial run and its first generated instance") and states exactly what the result contains (instance input, signed commitment, version pins, submission instructions). It clearly distinguishes the Pact Trials flow from siblings like get_trial_status or submit_evidence.

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 explicitly says when to use this tool ("Take the Pact Trials: three fresh generated, deterministically graded challenges") and outlines prerequisites ("Registration token sufficient — no human step, no payment"). It does not explicitly name alternatives or exclusions, but the context is clear.

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