set_tier

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

Discloses auto-detection and potential payment requirement, but fails to mention side effects, error handling, or irreversible actions. With no annotations, more detail is expected for a mutation tool.

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?

Three concise sentences with front-loaded purpose. No redundant 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?

Adequately describes behavior and output for a single-parameter tool without output schema. Missing error cases or preconditions, but sufficient for most use cases.

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 coverage is 100% and parameter description already mirrors tool behavior. Description adds no new semantic information beyond what the schema provides.

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?

Description clearly states it subscribes, renews, or upgrades tier, with auto-detection based on allowance state. This distinguishes it from read-only sibling 'tier_status', though no explicit differentiation is given.

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?

Implies usage when changing tier, but no explicit guidance on when to use versus alternatives like 'tier_status' or 'allowance_create'. Lacks exclusion criteria or prerequisites.

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