activate_external_subsystem

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

Annotations already declare the mutation/destructive profile (readOnlyHint false, destructiveHint true, idempotentHint false), so the bar is lower. The description adds a genuine behavioral trait beyond the annotations: the refusal on native/abstract/base classes. It does not explain side effects of activating a subsystem or behavior when already active, keeping it from a 5.

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 short, dense sentences with the core action front-loaded, the constraint immediately after, and the return shape last. No filler.

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?

No output schema exists, yet the description discloses the return shape ({ class_name, activated }), and it covers purpose and the key guard rail for a single-parameter mutating tool. It stops short of addressing idempotency or state effects, which would round it out.

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 the single parameter is fully documented in the schema, so baseline is 3. The description adds only marginal narrowing (Blueprint-authored, non-native/non-abstract/non-base), which mostly echoes the schema's own constraint.

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 (activate) and resource (external USubsystem), names the exact underlying API, and specifies it works on Blueprint-authored subsystems only. This clearly distinguishes it from the sibling deactivate_external_subsystem.

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?

Adds a real applicability boundary — it will refuse native, abstract, and base classes — which tells the agent when the call will fail. However it does not explicitly route to alternatives (e.g., create_subsystem_class_bp or is_subsystem_class_active) or state prerequisites such as editor/PIE context.

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