create_collection

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

No annotations provided, but the description discloses important behavior: the first mode becomes default, and the return structure includes mode IDs for use with set_variable_value and set_variable_mode. It does not mention side effects or reversibility, but for a creation tool, this is adequate.

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 succinct: one sentence for purpose, one for return and usage, and two example calls. No extraneous information.

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 the tool has only two simple parameters, no output schema, and no annotations, the description covers the core information needed to use it correctly: what it does, what it returns, and how to use the return values.

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 covers both parameters fully (100% coverage), and the description adds value by clarifying that the first mode in the array becomes default, and with examples showing typical usage patterns.

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 clearly states the tool creates a VariableCollection with named modes, distinguishing it from siblings like create_variable (creates a single variable) and ensure_collection (which would create or retrieve).

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?

The description explains how to use the returned modeIds with other tools and provides examples, but does not explicitly state when to use this tool versus alternatives like ensure_collection, or when not to use it.

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