mix_create_plan

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

Annotations already cover the broad safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false). The description adds useful beyond-annotation context by stating the tool stores a plan and makes 'no project value changes.' However, it does not clarify side effects of repeated calls, whether an existing plan is overwritten, or what 'closed-union' means operationally.

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 short and front-loaded with the core action, and the 'no project value changes' clause is valuable. However, the term 'closed-union plan' is unexplained jargon, and the brevity borders on under-specification rather than effective conciseness for a tool of this complexity.

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?

Given a large schema, 23 operation variants, and many related plan/lifecycle tools, the description is too incomplete. It does not explain where the stored plan goes, how it is later retrieved or applied, what 'session-bound' implies for durability, or how this relates to mix_apply_plan and mix_get_plan. The presence of an output schema reduces the need to describe return values, but lifecycle and selection context are still missing.

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 only 25%, and the description provides no parameter-level guidance. It does not explain how title, rationale, operations, or session_fingerprint should be populated, nor does it help the agent understand the 23-way discriminated union inside 'operations.' The description must compensate for the sparse schema but does not.

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 ('Store') and a specific resource ('session-bound closed-union plan'), and explicitly clarifies that no project values change. This is clear and helps distinguish plan creation from plan application, though it does not name or contrast siblings like mix_create_gain_stage_plan or mix_apply_plan.

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 guidance about when to use this tool versus alternatives such as mix_apply_plan, mix_get_plan, processing_plan, or mix_create_gain_stage_plan. The phrase 'session-bound' hints at a lifecycle, but no explicit when-to-use, prerequisites, or exclusions are provided.

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