Add Symbol Property

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

Annotations already indicate destructiveHint=true and readOnlyHint=false, so the mutation aspect is covered. The description adds that it works on a .kicad_sym file and can 'update' existing properties, but it does not disclose whether an existing property is overwritten without warning or whether file modifications are permanent beyond what the destructive hint implies.

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 a single, front-loaded sentence that clearly communicates the tool's purpose without redundancy. It includes useful examples and the file type, making it efficient and well-structured.

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?

The tool has a rich input schema and an output schema, so the description does not need to explain return values. However, given the existence of a very similar sibling tool ('add_library_symbol_property'), the description lacks enough contextual detail to guide an agent in selecting this specific variant, and it omits any mention of side effects beyond the annotations.

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 covers all six parameters with descriptions, so schema_description_coverage is 100%. The description provides examples of property names but does not add meaningful semantic information beyond the schema, such as coordinate units or behavior of optional fields like 'hide' and 'position'.

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 the verb ('Add or update') and the resource ('custom property on a symbol in a .kicad_sym library file'), with examples like Manufacturer and MPN. It is specific and actionable, but it does not explicitly distinguish itself from the sibling tool 'add_library_symbol_property', which may perform a similar operation.

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?

No guidance is provided about when to use this tool versus alternatives such as 'add_library_symbol_property' or 'update_symbol_from_library'. The description only states what the tool does, not the context in which it should be chosen.

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