switch_controllers

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

Annotations already declare destructiveHint=true, openWorldHint=true and non-idempotent, so the safety profile is covered. The description adds genuinely new operational context: the policy allowlist gate and the possibility of human approval, both of which affect how an agent should plan the call. It stops short of explaining consequences (e.g. that deactivating a controller halts its control loop).

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, no filler, with the core action stated first and the constraint second. Everything present earns its place.

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?

An output schema exists so return values need not be described, and the approval/allowlist behavior is disclosed. Minor gap: for a destructive, non-idempotent mutation it does not say whether switching interrupts active motion, which is the main thing an agent must anticipate.

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 100% and both parameter descriptions already state the allowlist constraint, so the description adds no syntax, ordering, or mutual-exclusivity detail beyond the schema. Baseline 3 applies when the schema carries the parameter burden.

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?

States a specific verb pair (activate/deactivate) and resource (ros2_control controllers), making it trivially distinguishable from read-only siblings like list_controllers or get_robot_state. No ambiguity about what the tool does.

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 gives a hard precondition (allowlist membership) and warns a human may need to approve, which implies when the tool can be used. However it never states when to prefer this over alternatives or which situations require switching versus reconfiguration, so usage is only implied.

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