pcb_render_stackup

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

With no annotations, the description carries the full burden for behavioral disclosure. It states the rendering purpose but does not mention read-only safety, how the SVG output is delivered (inline vs file), error conditions, or whether an active session is required beyond the schema. This is a notable 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?

A single sentence front-loads the action and resource, includes specific layer details, and contains no wasted words. It is appropriately concise for such a straightforward tool.

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?

The description adequately conveys the core output but leaves ambiguity about the return format (e.g., SVG data vs file path) and any operational requirements beyond the session_id documented in the schema. Given the simple tool, this is acceptable but not fully complete.

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 sole parameter (session_id) has a descriptive schema entry ('Session ID from pcb_parse_layout') with 100% coverage. The description adds no additional parameter insight, so the baseline score of 3 is appropriate.

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 clearly identifies an action (Render), a specific resource (SVG cross-section of the PCB layer stackup), and the key content (copper, dielectric, solder mask layers with thicknesses). This distinguishes it from data-retrieval siblings like pcb_get_stackup or pcb_get_stackup_templates.

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 for visualizing the stackup but provides no explicit guidance on when to prefer this over alternatives, nor any exclusions or prerequisites beyond what the schema implies. It is clear but lacks explicit differentiation.

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