fpga_place_route

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

Describes the main action and output, but does not disclose side effects (e.g., whether it writes files or produces a routed netlist) or error conditions. Since annotations are absent, this is a partial disclosure.

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?

Few sentences, no fluff, directly states purpose, inputs, and output.

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?

Covers inputs, output summary, and resolution logic. However, without an output schema, it does not fully describe the return value or any other outputs, and it omits prerequisites like prior synthesis.

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?

All parameters are described in the schema, and the description adds context about the netlist origin (from fpga_synth) and the priority of explicit device/package over board preset.

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?

Clearly states it runs nextpnr place-and-route for iCE40/ECP5, from a Yosys JSON netlist, and describes the output (utilization and Fmax). It is distinct from synthesis, bitstream, and programming tools.

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?

Provides guidance on device/package resolution and points to fpga_boards for presets. It does not explicitly say when to use vs alternatives, but the place-and-route role is clear.

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