lib_set_pin_owner_part

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

With no annotations, the description carries the burden and does well: it states that only the library changes, that placed instances update on the next Update From Libraries, and that this produces an ECO. It does not cover permissions, undo behavior, or invalid pin handling, so it is strong but not exhaustive.

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 front-loaded and structured with Args and Returns sections, and the technical rationale earns its place. The Returns section partly duplicates the existing output schema, so there is some avoidable redundancy.

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 library mutation tool with no annotations and poor schema descriptions, the description supplies the missing semantic, usage, and side-effect context. The output schema exists, so return-value completeness is not an issue.

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, and it does: pin_designators is documented as comma-separated with an example, owner_part_id is defined as 0 or 1..part_count, and component_name explains the empty-string fallback.

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 uses a specific verb and resource: reassign pins on a multi-part symbol. It clearly distinguishes sub-part assignment from Part Zero assignment, which is the central purpose of the tool.

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 gives a clear condition for using Part Zero: supply pins on multi-part components, and explains the redraw/netlist-merge problem that motivates it. It does not explicitly compare this tool with sibling library-editing tools, so it falls short of full alternative-routing guidance.

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