set_symbol_property

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

With no annotations provided, the description effectively discloses the experimental nature, prerequisite environment variable, requirement for the file to be closed, and the return value (post-edit ERC report). This provides good insight into behavior beyond the name.

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?

The description is extremely concise, consisting of two sentences. The first sentence front-loads the purpose, and the second covers prerequisites and output. No unnecessary words.

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?

Given the tool has 4 required parameters and no output schema, the description covers essential behavioral aspects (experimental, prerequisites, return value) but lacks details on parameter meanings. It is adequate but incomplete.

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?

The input schema has 0% description coverage, so the description must compensate. It only mentions 'Value, Footprint, ...' as examples for the property parameter but does not clarify the meaning of 'value', 'project', or 'reference' parameters. This leaves significant ambiguity.

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 clearly states it sets a property on an existing schematic symbol, with examples like Value and Footprint. It uses a specific verb and resource, and while it doesn't explicitly differentiate from siblings, the purpose is unambiguous.

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 description provides context by noting it is experimental and requires the KICAD_MCP_ALLOW_SCHEMATIC_WRITE environment variable and the file to be closed in KiCad. However, it does not specify when not to use this tool or suggest alternatives.

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