SWMM-MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states that the storage node starts empty unless specified (via 'initial_depth'), which adds useful context about default behavior. It mentions the return value ('success message or error description'), but lacks details on permissions, side effects (e.g., impact on model integrity), or error conditions. This is a moderate effort but leaves gaps for a mutation tool.

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 that are front-loaded: the first covers the core action and key parameters, and the second addresses return values. There's no wasted text, but it could be slightly more structured (e.g., explicitly listing parameters). Overall, it's efficient and well-sized for the tool's complexity.

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 5 parameters with 0% schema coverage, no annotations, and an output schema (which handles return values), the description is moderately complete. It covers the basic purpose and some behavioral traits but misses parameter semantics and usage guidelines. For a mutation tool with multiple parameters, this leaves significant gaps, though the output schema reduces the need to explain returns.

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 for all 5 parameters. It only implicitly references 'storage_volume_cuft' ('specified volume') and 'initial_depth' ('start empty'), leaving 'model_name', 'junction_name', and 'max_depth' unexplained. The description adds minimal meaning beyond the schema, failing to clarify parameter roles or constraints, resulting in inadequate documentation.

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 action ('Replace a junction with a cylindrical storage node') and resource ('junction'), specifying the type of storage node and that it can have a specified volume. It distinguishes from siblings like 'change_conduit' or 'change_storm' by focusing on storage nodes rather than conduits or storm-related changes. However, it doesn't explicitly differentiate from all siblings (e.g., 'duplicate_model' is unrelated).

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing junction), exclusions (e.g., when not to replace a junction), or refer to sibling tools like 'change_storm' for storm-related modifications. The only implicit context is that it operates on junctions, but this is insufficient for informed tool selection.

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