Encode or decode text with the ROT13 cipher or a custom ROT-N rotation shift to obfuscate or recover simple ciphered messages.
Apply ROT13 (or ROT-N) cipher to text.
| Name | Required | Description | Default |
|---|---|---|---|
| text | Yes | Text to encode/decode. | |
| shift | No | Rotation amount (default 13). |
Changes observed during successful MCP inspections.
v0.1.11Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It does not state whether the operation is reversible, how non-alphabetic characters are handled, whether case is preserved, or what the output looks like. It only names the cipher, leaving key behavioral traits implicit.
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, front-loaded sentence that wastes no words. It efficiently communicates the core operation without unnecessary elaboration.
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, deterministic transformation tool with a fully described schema, the description is largely complete. It lacks any note on output format, but the operation's nature makes the return value self-evident, so the gap is minor.
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 both parameters are already documented in the schema. The description's mention of 'ROT-N' adds minor clarification that the shift parameter allows arbitrary rotation values, but this is already conveyed by the schema's 'Rotation amount (default 13)'. Baseline 3 is appropriate.
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 operation ('Apply ROT13 cipher to text') and names the exact algorithm, making it distinguishable from sibling cipher tools like atbash_process or vigenere_process. However, it does not explicitly differentiate itself from alternatives or describe the resource beyond 'text'.
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 gives no guidance on when to use this tool versus other encoding or cipher tools. It merely states what the tool does, with no conditions, alternatives, or exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.