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

With no annotations at all, the description carries the full burden, and it does disclose two meaningful traits: requestKey provides idempotency, and uncertain calls are never automatically retried (implying side effects and that the agent must follow up via execution_status). However, it says nothing about what the call mutates, what permissions are needed, what gets returned, or what 'uncertain' means operationally.

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 with no filler, and the idempotency instruction is front-loaded after the purpose statement. The terseness comes at the cost of clarity around 'other protocol', but there is no padding.

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?

This is a high-complexity tool: four parameters, a nested sourceCheck object, no annotations, and no output schema. Two sentences cannot cover the shape of 'arguments', how contractId is sourced, or what a caller should do after an uncertain failure — all of which the description would need to supply.

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 only 25% — only sourceCheck is documented. The description adds real meaning for requestKey (must be stable) but leaves contractId and the free-form arguments object completely unexplained, so three of four parameters lack semantic guidance in either source.

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 verb 'Execute' is clear and the object is broadly named ('a pinned capability on the other protocol'), but 'other protocol' and 'pinned capability' are undefined jargon. It does not distinguish itself from siblings like discover or execution_status, so an agent must infer that this is the invocation step of a discover → execute → status workflow.

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?

The description gives an implementation instruction ('use a stable requestKey') and a caveat about retries, but never states when to call this versus execution_status or how to obtain a contractId (presumably via discover). No explicit when-to-use or when-not-to-use guidance is offered.

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