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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description still adds real context: it is an indirection layer that can invoke tools not present in the listing, it enforces a read-only filter, and argument shape is defined by the target tool rather than this one. It does not say what happens if a write tool name is passed or whether the target tool's own permissions still apply, which is the remaining gap.

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?

Three short sentences, front-loaded with the action and scope, then the read-only constraint, then the argument contract. Every clause carries information; nothing is restated from the title or schema.

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?

For a meta-dispatch tool with no output schema, the description covers everything needed to invoke it correctly: what it does, what it refuses, where the sibling for writes lives, and where to find the argument schema. Nothing material is missing.

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 baseline would be 3, but the description adds meaning beyond the schema: 'name' must be a full gateway name of a read-only tool, and 'arguments' must conform to that target tool's own input schema (obtainable via find_tools). That clarifies the dynamic, non-obvious contract of the arguments object, which the schema alone does not.

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 ('run a read-only tool from any allowed pack by its full name') plus a concrete example (hub_find_low_stock), and its dispatcher nature is unmistakable. It distinguishes itself from call_write_tool directly, so an agent can route without opening schemas.

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 names when to use this tool (read-only tools, including unlisted ones) and when not to (tools that change data go through call_write_tool), and points to find_tools as the source of the target tool's argument schema. Both the routing condition and the setup step are stated, not inferred.

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