Create an Assist pipeline

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

Annotations already declare readOnlyHint=false and idempotentHint=false, but the description adds genuinely useful behavior beyond the hints: engine params are entity IDs, not free-form names, they must already be installed, and re-using a name yields a second pipeline with a distinct HA-assigned ID. It adds no permission/error-handling detail, so it is strong but not exhaustive.

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?

Front-loads the create action and then uses labeled blocks (Use when / Not for / Returns / Limits) that make scanning trivial. Every sentence carries information; nothing is redundant 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?

With 11 parameters, an output schema, and full annotation coverage, the description supplies everything the agent still needs: the create semantics, the sibling to avoid, the discovery prerequisites, and the create-twice caveat. Return-value detail is minimal precisely because an output schema exists.

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 100%, so the baseline is 3, but the description adds value by clarifying that engine parameters are provider entity IDs (stt.*, tts.*, wake_word.*) rather than human-readable names and by pointing to the list_*_engines tools for discovery. It does not document defaults or the conversation_engine fallback, which the schema covers.

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 ('Create a new Assist pipeline') and even names the underlying WS command (assist_pipeline/pipeline/create). It is clearly distinguishable from siblings like voice_update_pipeline, voice_list_pipelines, and voice_set_preferred_pipeline.

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?

Contains explicit 'Use when' and 'Not for' clauses, routing existing-pipeline changes to voice_update_pipeline. It also names the four discovery tools the agent must call before supplying engine entity IDs, so the prerequisites are unambiguous.

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