compare_modelsSend one prompt to 2-4 Zerouter models in parallel and receive each response with token usage, latency, and estimated cost. Requires ZEROUTER_API_KEY.
Send the same prompt to 2-4 Zerouter models in parallel and return each answer with token usage, latency and estimated cost. Requires ZEROUTER_API_KEY.
| Name | Required | Description | Default |
|---|---|---|---|
| models | Yes | 2 to 4 model IDs | |
| prompt | Yes | ||
| system | No | ||
| max_tokens | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=false and openWorldHint=true; the description is consistent with both and adds genuinely new context — parallel fan-out execution, an auth requirement (ZEROUTER_API_KEY), and that each answer carries token usage, latency, and estimated cost. It stops short of stating rate limits or what happens if one model fails mid-fan-out.
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 tight sentences, front-loaded with the core action and return contents, then the prerequisite. Every clause carries information and nothing is redundant.
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 does its job by enumerating the returned fields (answer, token usage, latency, estimated cost) and the auth prerequisite. The only gap is guidance on the two undocumented optional params (`system`, `max_tokens`).
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 description coverage is only 25%, so the description is expected to compensate. It reinforces the `models` count (2-4) and 'same prompt' semantics, which merely restates the schema's minItems/maxItems, and says nothing about `system` or `max_tokens`.
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 ('send'), resource ('the same prompt to 2-4 Zerouter models'), and mechanism ('in parallel'), plus the shape of the output. The fan-out comparison semantics make it inherently distinct from the single-model `chat` sibling and from `list_models`/`get_pricing`.
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?
Usage is implied by the multi-model comparison framing and the 'Requires ZEROUTER_API_KEY' prerequisite, but nothing states when to prefer this over `chat` or explains the cost/rate implications of fanning out. No explicit alternatives or exclusions are given.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.