write_tag

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

With no annotations, the description carries full burden. It states the value is sent as-is and gateway handles type coercion, which provides some behavioral context. However, it does not disclose other traits like whether the write is synchronous, reversible, or has side effects.

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 concise with two sentences plus structured Args. Every sentence provides necessary information without fluff. It is front-loaded with the primary action and requirement.

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 two-parameter tool with an output schema, the description covers purpose, parameters, and a key behavioral note. It lacks mention of error scenarios or the output format, but the output schema exists so it is not required.

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 coverage is 0%, so description compensates well. It explains tag_path with an example and clarifies that value is a string representation for coercion, adding meaning beyond the schema's type definition.

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 writes a value to a tag on a live Ignition gateway. The verb 'write' and resource 'tag' are specific, and it distinguishes from sibling tools like read_tag.

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 mentions a prerequisite (server started with --gateway-url) but does not provide explicit guidance on when to use this tool versus alternatives. However, the context of writing tags is clear enough for correct selection.

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