lib_probe_designator

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

With no annotations, the description explicitly declares "Read-only" and enumerates the exact return fields with their units (native TCoord), which is meaningful behavioral disclosure. It does not say what happens if the footprint is not found or how library resolution defaults are chosen, leaving some gap for a tool carrying the full burden.

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?

Front-loaded with the one-line purpose, followed by read-only status, then the payload, then the return shape. Slight redundancy in re-listing return keys that an output schema already covers, but nothing is wasted.

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?

Because an output schema exists, repeating the return keys is a bonus rather than a necessity, and the behavioral side is covered. The input side is the gap: for a two-parameter tool with zero schema coverage, the description should say how library_path resolves and what footprint_name must match.

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% and the description mentions neither footprint_name nor library_path. The nullable library_path default in particular is left unexplained, so an agent cannot tell which library is searched when it is omitted.

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?

States a specific verb and resource: "dump one footprint's raw designator geometry," and frames it as a diagnostic probe of designator measurement. An agent can tell this is a read-only geometry inspection, though it never distinguishes itself from close siblings like lib_probe_footprint or lib_get_footprint_primitives.

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?

Gives a concrete triggering condition: use it to establish what IPCB_Text.BoundingRectangle actually measures before trusting it to centre anything. That is a clear when-to-use, but there are no exclusions or named alternatives for the general footprint-inspection case.

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