get_identities

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

With no annotations, the description fully shoulders the behavioral disclosure burden. It specifies that physical Matter devices return the full set while logical devices report only id + names, and it explains that the id is a one-way hash, making this tool the only way back to node_id/endpoint_id. This level of detail goes well beyond a minimal description.

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 compact and information-dense. It front-loads the main purpose, lists attributes, then covers the use case and id behavior. Every sentence contributes value with no redundancy or fluff.

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?

Given that an output schema exists, the description correctly avoids repeating return field structure. It covers the tool's main behavior, the physical vs. logical device distinction, and the special id decoding behavior. For a single-parameter, read-only tool, this is complete enough for proper selection and invocation.

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 input schema has a single optional id property with no description (0% coverage), so the description must compensate. It does so excellently by explaining that providing id returns just that device and decodes the hash back to its node_id/endpoint_id and identity. This is exactly the semantic meaning an agent needs to use the parameter correctly.

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 clearly states the tool returns hardware identity for every device, listing specific attributes such as vendor, product/model, versions, serial number, and Matter device-type ids. It distinguishes itself by mentioning the ability to decode a dev_ id back to node_id/endpoint_id, which is not evident in sibling tools like get_devices or get_status.

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 provides a concrete use case: 'Use to tell apart bridged children of one hub (e.g. Aqara sensors) that changed IDs after a re-pairing.' It also explains the behavior when an id is given. However, it does not explicitly compare with alternative tools or state when not to use this tool, so it falls short of a 5.

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