build_chain

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

Annotations already declare a non-destructive, non-read-only, closed-world mutation. The description adds that the chain is built 'from whatever is installed,' which usefully signals that it selects from installed plugins or devices. However, it does not disclose whether an existing chain is replaced or appended to, what happens when no suitable installed device exists, or how the target track is affected.

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 a single front-loaded sentence with no filler. The purpose examples are compact and useful. It could be slightly better structured by separating the usage condition from the list of purposes, but it is efficient overall.

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?

Although an output schema exists and annotations cover basic safety, the description is incomplete for a three-parameter mutation tool with zero schema description coverage. It omits how to choose between this and sibling chain/effect tools and does not explain track_index or track_type, which are essential to invoking the tool correctly.

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 0%, so the description must carry parameter meaning. It gives example values for 'kind' (vocal, piano, strings, cello, bass, drums, bus, master), which adds useful context. But it says nothing about 'track_index' or the 'track_type' parameter and its 'track' default, leaving two of three parameters undocumented in both schema and description.

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 states a specific verb and resource: 'Build an effect chain by purpose.' It also gives example purposes such as vocal, piano, strings, cello, bass, drums, bus, and master, which makes the tool's intent recognizable. It does not explicitly distinguish itself from nearby tools like add_effect or apply_chain_recipe, so it falls short of a 5.

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?

There is no explicit guidance on when to use this tool instead of alternatives such as add_effect, insert_device, load_instrument_or_effect, or apply_chain_recipe. The phrase 'by purpose' implies usage but does not tell the agent which situations select this tool over its siblings.

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