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

Goes well past the annotations: it warns the call can mutate the service's data, that non-local hosts are refused, that each call costs one metered execution, and it describes the async contract (inline result within ~2s, otherwise poll operation_status/operation_output and do not resend). That is exactly the operational context the destructive/idempotent hints do not convey.

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 trigger condition, then layers scope limits, prerequisites, cost, and result handling in four tight sentences with no filler or repetition.

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?

Handles the hard parts of a 9-parameter, nested, no-output-schema tool: async result retrieval, metering, host restriction, and retry guidance. It leaves the notion of an 'approved service' (how approval is established) and failure/refusal modes largely unexplained.

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; the description still adds value by tying sessionId to execution_session_open, specifying that operationId must be new per call, and framing the call against the metering model. It does not add meaning for url/body/headers beyond what the schema already documents.

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 (send) plus the exact method set (POST/PUT/PATCH/DELETE) and the resource (approved local service), which cleanly separates it from the sibling localhost_get. An agent can select it 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?

Opens with an explicit trigger ('Use this when the user asks to send...') and names prerequisites (sessionId from execution_session_open, a new operationId), plus the metering cost. It never explicitly routes GET traffic to localhost_get, so the exclusion is only implied by the method list.

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