List installed blueprints

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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds real operational context on top: it discloses the underlying `blueprint/list` WebSocket command via `ha._ws_call`, that nothing is read from disk, and that the call blocks for the round trip with a default 10 second wait. That timeout/blocking behavior is exactly the kind of trait annotations cannot convey.

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?

Purpose is front-loaded in the first sentence, followed by compact labeled sections (Use when / Returns / Limits). Every sentence carries information; nothing is redundant padding despite the multi-line length.

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?

Even though an output schema exists (so Returns needn't be spelled out), the description proactively summarizes the return shape, and adds mechanism, usage trigger, and a blocking/timeout caveat. For a low-complexity single-parameter list tool this is more than sufficient.

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 single 'domain' parameter is fully documented in the schema itself (type, default, folder semantics). The description restates the domain scoping ('for the given domain') but adds no syntax or format detail beyond the schema. Baseline 3 is appropriate.

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 (List), resource (installed blueprints), scope (for a domain), and mechanism (over the WebSocket API). An agent can distinguish it from blueprints_import_blueprint, blueprints_save_blueprint, blueprints_delete_blueprint, and blueprints_substitute_blueprint purely from the description.

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?

Explicitly names the trigger condition ('Use when: enumerating what blueprints exist under /config/blueprints/<domain>') and ties it to the sibling actions that follow (importing, substituting, deleting). It leaves nothing to inference about when this tool is the right one.

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