pcb_list_items

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds useful context beyond that: it reports units (mm and degrees), KiCad layer names, and item ids, plus a pagination cue. It stops at 3 because it never describes result shape semantics and the output schema already owns return values.

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?

Two sentences, no filler, with the core purpose front-loaded ahead of the pagination note. It is tight and appropriately sized for the tool's complexity.

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?

An output schema exists, so return-value details are not required here, and annotations cover the safety profile. What remains is a passable orientation for a filtered list tool; adding a note about which filters combine or the board_path default would have closed the remaining gap.

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 coverage is 57%, so the description should carry some of the load. It clarifies the 'kind' selector ('one kind') and page mechanics (limit/offset) but says nothing about the net, ref, layer, or board_path filters, leaving half the surface documented only in the schema. Baseline 3 fits.

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 clear verb (List) and resource (items of one kind from the board open in KiCad), adding scope detail (single kind) and output units (mm/degrees). It does not explicitly distinguish itself from nearby siblings such as pcb_net_stats or sch_list_components, so it stops short of a 5.

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 second sentence gives implied guidance for large boards ('page with limit and offset'), which tells the agent when pagination matters. However, there is no explicit when-to-use vs. alternatives routing, no mention of which sibling to prefer for aggregated stats, and no exclusions.

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