theory_modes

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

With no annotations, the description carries the burden of explaining behavior. 'List' clearly signals a read-only informational operation, and the response content is described. However, it does not disclose how the optional mode parameter affects the output, nor does it explicitly state that the tool has no side effects on the project.

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, well-front-loaded sentence with no filler. It states the action, scope, and output contents efficiently.

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 simple informational tool, the description covers the main purpose and expected output. It is incomplete only in that it does not describe what happens when the optional mode parameter is supplied, which is relevant for correct invocation.

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?

The schema already documents the only parameter as 'Optional: one mode', so baseline is 3. The description adds mild context by implying valid values are among the 7 church modes, but it does not explain the effect of providing mode on the returned list.

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 names a specific verb ('List'), a clear resource ('the 7 church modes'), and the exact content of the response (characteristic degree, vibe, typical use). It does not explicitly contrast itself with sibling theory_* tools, but the focus on modes is distinctive enough to make its purpose clear.

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?

No guidance is given about when to choose this tool over siblings like theory_scale, theory_diatonic_chords, or theory_borrowed_chords. The phrase 'typical use' refers to the content being listed, not to when the agent should invoke this tool.

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