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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds the one thing annotations cannot: the return shape ('names, the service each belongs to, and one line each'), which is valuable given there is no output schema. It omits pagination/limit behavior, keeping it below a 5.

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 purpose, then return shape, then routing, then the service vocabulary. The service list is long but it is load-bearing data, not filler.

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?

With no output schema, the description correctly takes on the burden of describing the return value and the valid service vocabulary, and it routes the agent to the follow-up tools. The only real gap is the undocumented limit parameter, which leaves the agent guessing at default and maximum result counts.

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 67% and there are no enums, but the description compensates by enumerating the valid service values (registry, exchange, wallet, router, ...), which the schema does not. The limit parameter remains undocumented in both places, so it is not a full 5.

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?

Specific verb+resource: 'Find the hub's tools by what you want to do.' It also distinguishes itself from siblings by naming describe_tools (schema) and invoke_tool (execution), so an agent can place it in the tool-discovery workflow without opening a 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?

It establishes the search → describe → invoke pipeline by stating what describe_tools and invoke_tool do, which tells the agent when to move on from this tool. It does not explicitly state exclusions (e.g., that this only searches tools, not agents, despite a sibling search_agents), so it falls short of a 5.

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