Name: evilissimo/design-by-contract
Rating: 92 (1 reviews)
Author: evilissimo

evilissimo/design-by-contract

Analyze code to suggest and add Design by Contract specifications (preconditions, postconditions, invariants, semantic invariants) in any language. Trigger on: "Design by Contract", "DBC", "preconditions", "postconditions", "class invariants", "code contracts", "formal specifications", "document assumptions", "add contracts", "make this function safer", "define what this function guarantees", "add assertions to document behavior", Bertrand Meyer, Eiffel contracts, or when discussing invariants that should always hold. Do NOT skip for non-Eiffel code — DBC applies everywhere via assertions, type guards, properties.

1.05x

Quality

90%

Does it follow best practices?

Impact

95%

1.05x

Average score across 5 eval scenarios

Securityby

Passed

No known issues

Evaluation results

95%

11%

Harden Bulk Discount Logic

Criteria

Without context

With context

Structured analysis

77%

100%

Status markers

100%

Inputs outputs state

100%

Preconditions

100%

Postconditions

100%

Executable asserts

100%

Contract comments

100%

Crash early

100%

Bad input tests

100%

Good input tests

100%

False positive note

37%

97%

Contract a Payment Webhook Boundary

Criteria

Without context

With context

Prioritizes boundary

100%

Structured analysis

75%

100%

Preconditions

100%

Postconditions

100%

Semantic invariant

80%

100%

TS mechanism

100%

No any leakage

100%

Clear errors

100%

Request scoped

71%

57%

Bad cases

100%

Comments docs

75%

100%

97%

Bank Account Contracts

Criteria

Without context

With context

Class invariants

91%

100%

Preconditions init

100%

Preconditions methods

100%

Postconditions methods

100%

Invariant restoration

80%

100%

Semantic invariant

100%

Executable checks

100%

Type/static option

50%

Bad tests

100%

Good tests

100%

Summary counts

66%

100%

94%

Safer Pagination Contracts

Criteria

Without context

With context

Preconditions

100%

Postconditions

90%

100%

Rust mechanisms

92%

Type-level contract

30%

70%

Clear violations

100%

Known bad tests

100%

Valid tests

100%

False positives

100%

85%

Comments docs

100%

Caller guarantees

83%

Summary

83%

100%

95%

Go Inventory Reservation Contracts

Criteria

Without context

With context

Preconditions

100%

Postconditions

100%

Semantic invariant

100%

Go mechanisms

83%

100%

No silent nil

100%

Clear messages

100%

Request transaction

75%

Comments docs

100%

Bad cases

100%

Good cases

100%

Prioritization

75%

62%

Evaluated: about 1 month ago
Agent: Claude Code
Model: Claude Sonnet 4.6

Table of Contents

Harden Bulk Discount Logic Contract a Payment Webhook Boundary Bank Account Contracts Safer Pagination Contracts Go Inventory Reservation Contracts