check_routing_number

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 does disclose an important behavioral limit by specifying the check is mathematical (checksum only, not registry lookup), which is real value. However, it says nothing about permissions, error behavior, or what an invalid input yields.

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?

A single sentence with zero filler, and the scope qualifier is placed front and center. Nothing is wasted.

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?

An output schema exists, so return-value explanation is not required. Still, for a tool whose whole purpose is a binary check, the description never says what the check implies (e.g., checksum validity vs. account existence) or the input format, leaving modest gaps.

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?

With 0% schema description coverage on a single parameter, the description must compensate. Calling it an 'ABA routing number' implies the domain and expected identifier type, but it omits the 9-digit format and whether separators are accepted, leaving a gap the schema does not fill.

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 states a specific verb (Check) and resource (ABA routing number) and narrows the scope to the mathematical check digit, which cleanly separates it from siblings like validate_ach_file or parse_ach_file. It does not name a sibling explicitly, so it stops short of 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?

There is no explicit when-to-use, when-not-to-use, or alternative-tool guidance. The narrow scope implies this is a format-level check rather than full account validation, but the agent must infer that from 'check digit' alone, which is thin.

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