add_chord_progression

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that it 'returns the notes chosen' and that voice leading is applied, but for a mutation tool it omits critical behavior: whether existing notes are overwritten, what the 'replace' flag does, whether it requires a selected/existing MIDI item, and what happens on failure. Significant gaps for a write operation.

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 sentences, front-loaded with the action and inputs, and the return behavior is appended efficiently. Every clause earns its place and there is no 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 13-parameter mutation tool with no annotations and no output schema, two sentences are too thin. It should cover the replace/add semantics, the 'selected' item_id convention, and interaction with existing item content; as written an agent cannot confidently predict the side effects of calling it.

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 77%, so the schema already documents most parameters (key, voicing, rhythm, bass_octave, chord_length). The description restates the chord-symbol/Roman-numeral input and voicing/rhythm concepts but adds no syntax or constraint detail beyond the schema, which matches the baseline 3 for high-coverage schemas.

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 ('Writes a chord part') plus the accepted input forms ('chord symbols or Roman numerals with a key') and the two axes it controls (voicing, comping rhythm). This is clearly more than a restated name, but it never distinguishes itself from adjacent writers like write_bassline, write_melody, or harmonize_melody, so it stops short of the 5 bar.

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 when-to-use or when-not-to-use guidance and no named alternative. An agent must infer that this is the tool for chords versus write_melody or harmonize_melody entirely on its own, and nothing tells it about prerequisites such as needing an existing MIDI item.

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