Add Sheet Pin

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

Annotations already flag this as destructive (destructiveHint=true) and not read-only, so the safety profile is known. The description adds the key constraint that pinName must exactly match a hierarchical_label in the sub-sheet, and explains what sheet pins are. However, it does not mention potential failure modes, whether existing pins are affected, or any side effects beyond adding a pin.

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 two sentences, front-loaded with the action ('Add a pin...') followed by a crisp explanation of sheet pins and the matching requirement. No filler or redundant content.

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 covers the core operation and a critical constraint. With an output schema present, return values are handled there. It could mention prerequisites like having an existing sheet symbol, but the matching constraint implies the sub-sheet must exist, making this reasonably complete for a focused mutation tool.

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%, so the baseline is 3. The description reiterates the pinName matching constraint (already in the schema) but adds no new parameter-level semantics. It provides useful context about the parent-side role of the pin, but this does not meaningfully extend what the schema already documents.

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 a specific verb and resource: 'Add a pin to a sheet symbol block on the parent schematic.' It clearly distinguishes this from sibling tools like add_hierarchical_sheet (which adds the sheet itself) and add_schematic_hierarchical_label (which adds labels in the sub-sheet) by stating these are parent-side connection points.

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 clear context: this is for parent schematic pins that correspond to sub-sheet hierarchical labels. It implies the workflow (must have a sub-sheet with matching labels) and does not explicitly name alternatives or exclusion criteria, but the context is sufficient for an agent to select this tool over related ones.

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