invoke_service

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

With no annotations provided, the description discloses critical behavioral traits: the need for explicit authorization (THINGWORX_ALLOW_INVOKE=true) and that services can execute potentially destructive actions (PLC commands, scripted workflows, downstream calls). It does not cover all aspects like return format or error handling, but adds significant value.

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 two sentences, front-loaded with the main action, and every word contributes essential information. No filler or redundancy.

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 complexity (invocation of arbitrary services with potential side effects) and lack of output schema, the description covers safety and authorization but omits details on return value, error states, or typical success/failure behavior. It is adequate but not fully complete.

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 the baseline is 3. The description adds no extra meaning beyond what the schema already states for each parameter (thing_name, service_name, parameters). It merely restates that parameters are optional.

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 (invoke) and resource (a named Service on a Thing), distinguishing it from sibling tools like read_property or write_property, which handle data access rather than action execution.

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 explains that the tool is gated by an environment variable and is separate from write operations, implying it should be used when authorized for executing actions. However, it does not explicitly contrast with sibling tools or specify when not to use it.

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