z2m_list_devices

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds the behavioral nuance that collect_seconds will wait before answering, and notes the tool is read-only despite the waiting. This goes beyond the annotations by explaining the side effect of a parameter, but it doesn't delve into other behaviors like pagination or failure modes. Given annotations cover safety, this is adequate.

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?

The description is concise and front-loaded, starting with the core action and resource. Each sentence serves a purpose: the field list, the read-only note, the use cases, the alternative guidance, and the return format. No filler words; every sentence earns its place.

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?

The description includes the return structure '{total, returned, capabilities, devices[]}', which is essential given no output schema exists. It also covers common user intents (offline devices, weak signal) and distinguishes from sibling tools. While it doesn't explain every parameter, the schema handles that. This is reasonably complete for a list tool.

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 high (88%) with descriptions for most parameters. The description adds value by explaining that collect_seconds waits to populate live fields like linkquality, battery, and OTA, and hints at the 'weakest signal' use case which aligns with sort_by and only_problems. It doesn't repeat each schema description but enriches the meaning of key parameters.

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 immediately states the tool lists Zigbee devices with administrative detail and enumerates the specific fields (type, model, vendor, power source, link quality, battery, availability, last_seen, interview state, OTA updates). It also distinguishes itself from siblings by naming z2m_health_report and z2m_get_device as alternatives, making its unique purpose clear.

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 gives explicit use cases: 'Use this to answer which devices are offline or which have the weakest signal'. It also provides clear alternatives with specific conditions: 'Prefer z2m_health_report for a prioritised summary of everything wrong at once, and z2m_get_device when you need one device's exposes, options or bindings.' This is excellent when-to-use and when-not-to-use guidance.

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