MCP Server for Loop Invariant Induction Prover Skill - Formally validates loop correctness through initialization, preservation, and postcondition implication
Single tool with minimal definition quality. Tool name 'verify_loop_invariant' lacks action verb clarity (should be 'verify_' prefix is present but compound name is awkward). Description is adequate (67 chars) but generic. No output schema documented. No error handling guidance. Tool appears hardcoded to a specific algorithm (Gauss summation) rather than accepting algorithm parameters, severely limiting reusability.
Verify initialization, preservation, and postcondition across test inputs
Input parameter 'n_values' lacks description. LLMs cannot infer that this is a list of test case values.
No output schema documented. Tool returns a dict with keys like 'initialization_ok', 'preservation_ok', 'postcondition_ok', 'all_passed', 'tested_inputs_count' but LLMs have no formal specification of return structure, types, or field meanings.
Tool is hardcoded to verify a single algorithm (Gauss summation). Precondition, loop_guard, loop_body, invariant, and postcondition are all lambda functions baked into handle_call(). Tool cannot accept arbitrary loop specifications, it only tests one fixed algorithm. This violates single-responsibility and reusability principles.
No error handling or recovery guidance. If verification fails, the tool returns a dict with 'all_passed': False but provides no actionable error message, no indication of which step failed, and no guidance on what the LLM should do next.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | F | 41 | 2026-07-28+ | v2 |
Tool name 'verify_loop_invariant' is compound and domain-specific. For an LLM unfamiliar with formal methods, the name does not clearly convey what the tool does or when to use it. Consider 'verify_loop_correctness' or 'test_loop_invariant' with a clearer description.