control_thermostat

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses the dual-behavior nature of combined devices (plug vs thermostat), which is the key subtlety. However, it doesn't disclose the effect of turn_on/turn_off on non-combined thermostats, error behavior, or whether set_mode with 'off' disables the thermostat. Decent but not rich behavioral transparency for a mutating tool.

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, zero waste. Every clause earns its place: the first states the tool's scope, the second clarifies the critical nuance about combined devices. Front-loaded with the primary purpose.

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?

A mutating tool with no annotations and no output schema has gaps. The 100% schema coverage and enum-rich parameters help, and the combined-device clarification is valuable. However, missing guidance on what happens for turn_on/turn_off on non-combined devices, and no behavioral contract about setpoints (ranges, units like Celsius/Fahrenheit) leaves room for the agent to make wrong calls. Adequate but not comprehensive.

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 100%, so the schema already documents all four parameters thoroughly, including enums and per-parameter purpose. The description adds the plug-vs-thermostat semantic distinction for turn_on/turn_off, which is genuinely additive. Baseline 3 is appropriate since the schema does the heavy lifting and the description adds one useful clarification.

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 states the tool controls a Wyze thermostat with a specific verb (control) and resource (thermostat). It usefully differentiates the plug vs thermostat behavior for combined devices, which distinguishes this from control_plug/control_switch siblings. However, the purpose is somewhat generic ('Control a Wyze thermostat') without enumerating the specific actions supported, though those are in the schema.

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 explicitly clarifies when turn_on/turn_off applies (only combined devices, controlling the plug/heater power) versus temperature actions controlling the thermostat. This provides clear context on how to select actions. It doesn't explicitly name sibling tools for exclusion, but the wiring of action-to-device-type behavior is helpful guidance that reduces misuse.

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