List ESPHome devices

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds value beyond that by disclosing the payload content (configuration filenames) and its role as prerequisite data for other tools, though it says nothing about pagination, counts, or failure modes.

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?

One front-loaded sentence that names the operation, its scope, and the returned payload without any filler.

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?

For a zero-required-param list tool with no output schema, the description covers purpose, output content, and downstream use. It is close to complete, only missing minor return-shape detail such as empty-list behavior.

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% and the single instance_id parameter is fully documented in the schema, including the refusal-on-mismatch behavior. The description adds no parameter-level meaning, so the baseline 3 applies.

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+resource ('List devices/configurations known to the ESPHome dashboard') and scopes it to the ESPHome domain, distinguishing it from the generic ha_list_devices sibling. It also names what the result contains (configuration filenames).

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 parenthetical 'needed by the other ESPHome tools' establishes this as the discovery/enumeration step before other ESPHome operations, which is real usage guidance. It stops short of explicit when-not conditions or naming alternative list tools.

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