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paypal-integration

Master PayPal payment integration including Express Checkout, IPN handling, recurring billing, and refund workflows.

51

Quality

56%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Medium

Suggest reviewing before use

Fix and improve this skill with Tessl

tessl review fix ./skills/paypal-integration/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

46%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This skill provides broad coverage of PayPal integration topics with mostly executable code examples, but suffers from significant verbosity by inlining extensive code that should reside in the referenced (but missing) bundle files. The workflow lacks explicit validation checkpoints critical for financial transactions, and the core concepts section explains things Claude already knows. The mismatch between the deprecated paypalrestsdk and the modern Orders v2 API in the Quick Start creates confusion.

Suggestions

Move the bulk of the code examples into the referenced resource files (e.g., assets/paypal-client.py, assets/ipn-processor.py) and keep only a minimal Quick Start example in SKILL.md with clear pointers to those files.

Remove the 'Core Concepts' section entirely or reduce it to a single sentence per product — Claude already understands PayPal's product categories.

Add explicit validation checkpoints to workflows: verify payment amount matches expected amount before fulfilling orders, validate IPN sender IP, and add a retry/recovery flow for failed captures.

Fix the Quick Start to use a consistent API approach — either the paypalrestsdk or direct REST API calls, not both with incompatible patterns.

DimensionReasoningScore

Conciseness

The skill is significantly verbose. It inlines hundreds of lines of code that should be in referenced files (which are listed in Resources but not provided). The 'Core Concepts' section explains basic PayPal product categories Claude already knows. The 'Common Pitfalls' and 'Best Practices' sections largely restate obvious points.

2 / 5

Actionability

The code examples are mostly executable and cover the key workflows (checkout, IPN, subscriptions, refunds). However, the Quick Start mixes the deprecated paypalrestsdk library with the modern REST API approach, and the backend verification code uses Payment.find/execute which doesn't align with the Orders v2 API used in the frontend. Minor gaps like undefined helper functions (is_transaction_processed) reduce full executability.

4 / 5

Workflow Clarity

Individual code blocks show steps but there's no overarching workflow sequence with explicit validation checkpoints. Payment processing involves financial transactions (destructive/batch-like), yet there are no explicit verification steps between create and capture, no validation of payment amounts against expected values, and the IPN flow lacks a clear error recovery loop beyond basic verification. The testing section acknowledges manual steps but doesn't provide a clear validation workflow.

3 / 5

Progressive Disclosure

The skill references multiple resource files (references/express-checkout.md, assets/paypal-client.py, etc.) but none are provided in the bundle. Meanwhile, the SKILL.md itself inlines ~300+ lines of code that should live in those referenced files. The content that's inline duplicates what the references claim to cover, making the structure contradictory and poorly organized.

2 / 5

Total

11

/

20

Passed

Description

66%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description effectively names the domain (PayPal) and lists several concrete integration features, making it reasonably specific and distinctive. However, it lacks a 'Use when...' clause, which is a significant gap for skill selection in a multi-skill environment. The use of 'Master' as the leading verb is slightly unusual but acceptable as third-person imperative.

Suggestions

Add a 'Use when...' clause with trigger phrases like 'Use when the user asks about PayPal integration, payment processing with PayPal, IPN webhooks, or PayPal subscription billing'.

Include additional natural trigger terms such as 'PayPal API', 'subscription', 'payment gateway', 'checkout flow', and 'PayPal SDK' to improve keyword coverage.

DimensionReasoningScore

Specificity

Lists several specific actions: Express Checkout, IPN handling, recurring billing, and refund workflows. These are concrete PayPal integration features, though it could be more detailed about what each entails (e.g., webhook setup, subscription management).

4 / 5

Completeness

Has a clear 'what' (PayPal payment integration with specific features), but completely lacks a 'when' clause. There is no explicit guidance on when Claude should select this skill, which caps this dimension at 3 per the rubric.

3 / 5

Trigger Term Quality

Includes strong natural keywords like 'PayPal', 'payment integration', 'Express Checkout', 'IPN', 'recurring billing', and 'refund'. Missing some common variations like 'subscription', 'checkout flow', 'payment gateway', or 'PayPal API'.

4 / 5

Distinctiveness Conflict Risk

PayPal-specific terminology like 'Express Checkout', 'IPN handling', and 'PayPal' itself make this fairly distinct. Minor overlap risk with generic payment processing or Stripe integration skills, but the PayPal-specific terms reduce conflict significantly.

4 / 5

Total

15

/

20

Passed

Validation

90%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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