SWMM-MCP

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

No annotations are provided, so the description carries the full burden. It states the tool returns a list but does not disclose behavioral traits such as permissions needed, rate limits, error handling, or whether it's read-only (implied by 'Returns' but not explicit). This leaves significant gaps for a tool with no annotation coverage, warranting a 2.

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 appropriately sized with two sentences that are front-loaded: the first states the core purpose, and the second adds necessary context for 'object_type'. There is no wasted text, but it could be slightly more structured (e.g., bullet points for parameters), so it earns a 4 for efficiency with minor room for improvement.

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 2 parameters with 0% schema coverage, no annotations, but an output schema exists, the description is moderately complete. It explains the purpose and provides some parameter guidance but lacks behavioral details and full parameter semantics. The output schema mitigates the need to explain return values, but overall completeness is adequate with clear gaps, scoring a 3.

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 0%, so the description must compensate. It adds meaning for 'object_type' by providing examples ('node', 'link', 'subcatchment') and referencing another tool for a full list, which clarifies semantics beyond the bare schema. However, it does not explain 'model_name' or other parameter details, so it partially compensates but not fully, resulting in a baseline 3.

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 tool's purpose: 'Returns a list of objects in the output file for a given model and object type.' It specifies the verb ('Returns'), resource ('objects in the output file'), and scope ('for a given model and object type'). However, it does not explicitly differentiate from siblings like 'get_output_variables' or 'get_input_info', which limits it to a 4 rather than a 5.

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 implied usage guidance by referencing another tool ('model_output_variables') for a list of object types, suggesting when to use this tool for retrieving object lists. However, it lacks explicit when/when-not instructions or alternatives compared to siblings like 'get_output_variables' or 'get_input_info', so it earns a 3 for implied context without clear exclusions.

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