pcb_get_net_length

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

Annotations already declare the full safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the behavioral burden is light. The description contributes only the word 'routed,' which distinguishes from logical/manhattan length, but adds nothing about units, layer scope, or whether unrouted connections count.

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?

A single front-loaded sentence with zero waste and no filler. It is appropriately sized for the operation, though it is terse enough that a small clarifying clause (e.g., units) could have been added without bloat.

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 simple read tool with full schema coverage and annotations carrying the safety profile, only purpose needs stating, and it is stated. Remaining gaps are minor but real: no indication of units or whether the figure spans all copper layers versus a specific one.

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%, and each parameter (net, document, instance_id) is well documented in the schema itself, including how to obtain the document UUID and when instance_id is required. The description adds no parameter-level meaning, so the baseline of 3 applies.

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?

Names a specific verb (Get) and resource (total routed length of a net), which clearly distinguishes it from generic net readers like pcb_get_all_nets or pcb_get_net_primitives by indicating the returned metric. It does not, however, explicitly contrast itself with those siblings.

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?

Usage is implied: an agent can infer it should call this when a net's routed length is needed. There is no explicit when-to-use guidance, no exclusions, and no pointer to alternatives such as pcb_get_net_rules or pcb_get_net_primitives.

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