pcb_focus_board

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

No annotations exist, so the description carries the full behavioral burden, and it does the important part: it discloses that this mutates implicit global state that every other pcb_* tool reads, and that the obvious sibling (`app_set_active_document`) silently fails to set it. It does not cover failure modes (invalid path, non-PcbDoc) or whether focus persists across document closes, which keeps it short of a 5.

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 action, then the rationale, then the exception, then Args/Returns. The parenthetical list of affected tools (`pcb_get_components`, `pcb_delete_net`, …) is illustrative rather than exhaustive and costs a line, but it earns most of its space by making the blast radius concrete.

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 one-parameter state-setting tool this is complete: what it does, why it must be called before other PCB tools, the sibling that does not substitute for it, the argument format, and a pointer to the return shape (which the output schema also covers). Nothing needed to call it correctly is missing.

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 0%, so the description must supply the meaning itself, and the Args block does: shape/format (absolute path) and target type (.PcbDoc). That is the full semantics needed for a single required parameter, though it says nothing about path normalization or relative-path behavior.

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?

Specific verb and resource: 'Make a specific PCB the focused/current board.' It also preempts the closest sibling by naming `app_set_active_document` as the thing that does not work for PcbDocs, so an agent can distinguish the two without reading either schema.

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?

Explicit when-to-use: 'When several PcbDocs are open... Call this first.' It also carves out an exception where this tool is unnecessary (`pcb_place_components` already takes `board_path`), which is exactly the alternative-routing guidance the dimension asks for.

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