List devices

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe read profile is covered. The description adds that results come from the device registry and how filters match, but does not cover return format, pagination, or scope size. Modest added value over the annotations.

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 tight sentences with zero waste, efficiently front-loading the core action and then the optional filters. Nothing redundant or padded.

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 read-only list tool whose safety profile is carried by annotations and whose parameters are fully documented by the schema, the description is nearly complete. No output schema exists, so return values need not be explained, though scope/volume hints would have pushed it higher.

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 all three parameters are already documented, including the meaningful instance_id scope rule. The description's filter details (area id/name, search across name/manufacturer/model) largely restate the schema rather than adding syntax or format meaning.

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 and resource — 'List Home Assistant devices from the device registry' — and identifies the source registry, which implicitly separates it from esphome_list_devices. However it does not explicitly name a sibling or clarify how it relates to ha_list_entities, so no explicit sibling differentiation.

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?

Usage context is implied by the optional filters ('Optionally filter by area... and/or a search string'), which hints at how to narrow results. There is no explicit when-to-use vs alternatives guidance or exclusion criteria relative to the many sibling list tools.

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