model_router_status

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

readOnlyHint=true already tells the agent this is a safe, non-mutating read, so the annotation carries the safety profile. The description adds the useful content signal that results span three distinct concerns (config, last pass, per-role route), but says nothing about freshness, cost, or whether it triggers a routing pass as a side effect.

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 clause with zero filler, and the three returned elements are listed up front. It is on the terse side for a status tool, but nothing is wasted.

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 an output schema present and no parameters, the description does not need to spell out return values, and it is adequate for a simple read. It is still thin on the one thing an agent must decide — when this status read is the right call relative to model_router_run and model_route_write.

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 no parameters, so there is nothing for the description to disambiguate and the baseline is 4. The schema is empty anyway, leaving no coverage gap to compensate for.

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 names the specific resource (model-router) and enumerates what is returned: config, last pass, and the current route of each auto role. That is far more informative than the bare name, though it is a noun phrase with no explicit verb and does not explicitly contrast with siblings like model_route_write or model_router_run.

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?

There is no statement of when to call this versus model_router_run (trigger a routing pass) or model_route_write (change a route). The 'status' naming only weakly implies 'read state before mutating', leaving the agent to infer the calling context from siblings.

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