use_tool

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

Annotations already declare destructiveHint=true, readOnlyHint=false, openWorldHint=true, and non-idempotent, so the risk profile is covered. The description adds meaningful context beyond that: the target's own identity, validation, authorization, timeout and response middleware all run, so this gateway is not a privilege escalation path. It stops short of describing error or failure behavior.

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?

Four sentences, front-loaded with the action and the prerequisite chain, then the safety clarification and the recursion exclusion. The middleware enumeration is slightly long but each clause carries a distinct behavioral fact worth keeping.

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?

No output schema exists, so the description should orient the agent on return expectations, which it only gestures at implicitly. For a five-parameter gateway with nested arguments, it otherwise covers prerequisites, delegation semantics, and the key failure mode (recursive refusal) adequately.

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 100% with all five parameters documented, so the baseline is 3. The description only reinforces that arguments must be built from describe_tool output and that tool_name must be the exact name from list_tools, adding marginal value over the schema's own field descriptions.

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: invoke one public capability discovered via list_tools. It also carves out exactly what it is not ('a discovery gateway, not an authorization bypass'), which distinguishes it from siblings like list_tools, describe_tool, and the session tools.

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?

Explicit sequence: find the name with list_tools, inspect arguments with describe_tool, then pass the argument object here. It also states an exclusion — it refuses recursive use_tool calls — so the agent knows both when to use it and one case where it will not work.

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