set_tool_tier

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

Annotations already declare readOnlyHint=false and openWorldHint=false, so agents know this is a mutating, closed-world operation. The description adds that it narrows/widens the exposed tool list and applies to the current session, which is useful context beyond the annotations. It doesn't disclose every side effect (e.g., persistence), but it's adequate given the annotation coverage.

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 core purpose, then usage guidance. Every word earns its place with no filler or redundancy. Efficiently structured for quick comprehension.

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 single-parameter, no-output-schema tool, the description fully covers what it does, when to use it, and the allowed parameter values. There is nothing critical missing for a 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?

Schema has zero description coverage for the parameter, but the description lists the enum values ('core', 'standard', 'full') and explains their effect (narrow/widen tool list). This fully compensates for the schema gap, making the parameter's meaning clear without needing to open the schema.

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?

Clearly states a specific action (override tier for current session) and the resource (exposed tool list), and explicitly names the three allowed values. It also distinguishes itself from plan_turn, the routine alternative, so an agent can immediately tell what this tool is for.

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?

Gives explicit routing: prefer plan_turn(model=...) for routine per-task use, use set_tool_tier only for explicit overrides, and provides a concrete example (escalate mid-task to 'full' after a capability-gated failure). This leaves no ambiguity about when to pick this tool over the alternative.

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