set_forwarding

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

Annotations already flag this as destructive and non-read-only, but the description adds valuable specifics: the operation replaces all forwardings, an empty array deletes all, and the tool reads and returns before/after state. This goes well beyond the structured hints and gives the agent a clear mental model of side effects.

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?

Two sentences, no filler, and the core action is front-loaded. The empty-array deletion case and the before/after return behavior are both essential and included without extra words.

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 mutation tool with no output schema, the description covers the destructive scope, the deletion edge case, timeout routing, and the return value nature. Combined with fully documented parameters and relevant annotations, an agent has enough context to invoke the tool correctly.

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%, with each parameter already described in the input schema, so the description is not required to repeat parameter details. It reinforces the semantics of forwardings ('replacement list', '[] removes every forwarding') but does not add meaningful new 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?

The description uses a specific verb ('replace') and a clear resource ('all forwardings for a phoneline'), and further clarifies scope with 'including timeout routing' and the empty-array deletion case. This makes it readily distinguishable from sibling tools like get_routing, set_dnd, and set_number_routing.

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 description implies when to use the tool: whenever a complete replacement of forwardings is desired, and explicitly documents the deletion use case with an empty forwardings array. However, it does not name or contrast any sibling tool, so guidance about when not to use it or which alternative to choose is left to inference.

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