calculate_bga_escape_routing

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

Annotations already establish this as a safe, deterministic, idempotent read-only computation, so the heavy behavioral burden is lifted. The description adds the standards basis (IPC-7095 Section 5.2), which is useful context, but says nothing about the return shape or units of the computed results despite there being no output schema.

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 dense sentence with no filler, and the core resource and computed quantities are front-loaded. It is slightly packed but every clause carries substantive meaning.

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 read-only parameterized calculation with all six parameters fully documented in the schema and safety covered by annotations, this is nearly complete for correct invocation. The only omission is any indication of what the computed output contains, which would have helped since no output schema exists.

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%, so every parameter is already documented in the schema and the baseline is 3. The description's mentions of fanout geometry, trace widths, and clearances loosely map to via/ball/trace parameters but add no syntax or default nuance beyond what the schema already states.

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 names a specific verb (Calculate) and resource (BGA escape routing) and then enumerates exactly what is computed: diagonal dogbone via fanout geometry, escape-channel trace widths/clearances, and minimum signal-layer requirements. This is precise enough to distinguish it from every sibling calculate_* tool, none of which cover BGA escape fanout.

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 domain phrasing ('escape channel', 'IPC-7095 Section 5.2') strongly implies when the tool applies, so usage is inferable, but there is no explicit when-to-use statement, no preconditions, and no named alternative among the many calculate_* siblings. It sits at minimum-viable guidance.

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