list_routing_rules

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

With no annotations supplied, the description carries the full behavioral burden; it does disclose account scoping and that only "active" rules are returned, which is genuine context. However, it says nothing about pagination, ordering, result volume, or permission requirements, leaving the agent to discover read behavior empirically.

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?

A single front-loaded sentence of nine words with zero filler; the key noun and scope appear immediately. Nothing could be removed without losing meaning.

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 zero-parameter list tool this is nearly sufficient, but with no output schema and no annotations the description never indicates what a routing rule record contains or how results are shaped. An agent knows what it will get conceptually but not what fields to expect.

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?

The tool takes zero parameters, so there is no parameter semantics to explain and the baseline of 4 applies. The description correctly signals that no filtering arguments are needed or accepted.

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 ("Lists") and resource ("routing rules") scoped to the account, which cleanly separates it from create_routing_rule and delete_routing_rule among the siblings. It does not explicitly name or contrast with an alternative list-style tool, so it falls short of a 5.

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 phrase "active under your account" implies the use case (discover existing routing configuration) and rules out account-wide cross-tenant queries, but there is no explicit when-to-use statement, no mention of what to do after listing, and no note on whether inactive rules are excluded. Usage is inferable rather than stated.

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