cf_email_routing_rules

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

No annotations are provided, so the description carries the full burden. 'List' implies a read-only, non-mutating operation and the parenthetical enumerates the returned data shape, which is genuinely helpful. However, it omits the zone identifier format, pagination behavior, and any auth/permission requirements for a tool with zero annotation coverage.

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?

One front-loaded sentence plus a short usefulness clause; nothing is padded and the resource is named first. The trailing sentence is slightly filler but still earns its place as usage context.

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 a read-only list tool, an output schema already present, and no nested objects, the description covers purpose and return content adequately. The remaining gap is the zone parameter's expected format, which the schema also fails to document.

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 single 'zone' parameter has 0% schema description coverage, so the description must compensate. 'For a zone' restates the parameter name without clarifying whether it expects a zone ID or name, or noting that it is optional (required=false with default ''). Adds minimal meaning beyond the schema.

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 (List) and resource (Cloudflare Email Routing rules for a zone), and even enumerates the returned content (matchers, forward actions, enabled status, priorities). It is clearly distinguishable in name and content from the closest sibling cf_email_destinations, though it never explicitly contrasts them.

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?

'Useful to inspect inbound routing for domains' implies the use case but gives no when-to-use/when-not conditions and no alternative tools to prefer over this one. The guidance 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.