brain_activate

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

With no annotations, the description carries the full burden. It clearly conveys a display action ('opens ... on screen') and implies no side effects via 'show the person a result.' It doesn't discuss edge cases, but for a simple UI-activation 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?

Two sentences, front-loaded with the action, and every word earns its place. No redundancy or 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?

For a simple tool with no output schema, the description covers what it does, when to use it, and gives a concrete example. It doesn't discuss errors or prerequisites, but those are likely unnecessary for a basic UI-opening action.

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?

The description adds no parameter information. The schema covers brainId with a helpful instruction, but thoughtId is completely undocumented. With 50% schema description coverage, the description should have compensated by explaining thoughtId, but it doesn't.

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 states a specific action with a clear resource: 'Opens a thought in the user's TheBrain app on screen.' It also provides a concrete use case ('show the person a result') that distinguishes it from sibling tools like brain_get_thought or brain_create_thought.

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?

It provides explicit context on when to call the tool: 'Call it to show the person a result — for instance a structure you have just created.' While it doesn't explicitly name alternatives or exclusions, the guidance is clear and actionable.

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