render_brain

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

With no annotations, the description carries the behavioral disclosure burden and does it well: it reveals output format (PNG), coordinate system details (axial view, Z axis discarded), legend inclusion, connection threshold behavior, and the error case. It does not mention side effects, but as a rendering tool this is a minor gap.

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?

The description is one dense sentence with no filler, front-loading 'Imagen PNG real' and then specifying projection, coloring, connections, and error behavior. The repeated use of 'real' is slightly heavy but serves to emphasize the contrast with synthetic/network views.

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 3-parameter tool with no annotations and no output schema, it covers output format, coordinate handling, coloring, thresholding, and error behavior. It is less complete because it omits connection_type semantics and does not explicitly guide selection relative to render_network.

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 0%, so the description must compensate, but only min_weight is explained ('connections above min_weight as thin lines'). atlas_id is inferable from the tool's purpose, while connection_type receives no explanation of its allowed values or effect, leaving a significant parameter gap.

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 opens with 'Imagen PNG real' and specifies a 2D axial atlas projection with real X/Y coordinates, coloring by functional network, and thresholded connection lines. This gives a clear verb+resource+output and distinguishes it from siblings like render_network by focusing on atlas projection, though it does not explicitly name alternatives.

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 implies usage: call this to get a real PNG image of an atlas projection. However, it does not explicitly state when to use this tool over render_network or other visualization siblings, and the only selection-related hint is the error condition when no real region is loaded.

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