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device-integrity

Verify device legitimacy and app integrity using DeviceCheck (DCDevice per-device bits) and App Attest (DCAppAttestService key generation, attestation, and assertion flows). Use when implementing fraud prevention, detecting compromised devices, validating app authenticity with Apple's servers, protecting sensitive API endpoints with attested requests, or adding device verification to a backend architecture.

Quality

91%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Passed

No findings from the security scan

The canonical home for this skill is dpearson2699/swift-ios-skills

SKILL.md
Quality
Evals
Security

Quality

Content

85%Weight 40%Scale 1-5

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

A well-structured skill: executable code for every client-side phase, explicit sequencing with validation checkpoints and error-recovery loops, and a genuine one-level-deep reference split. The main improvement opportunities are consolidating repeated generic pointers to the reference file and defining the few helper symbols used in code examples.

Suggestions

Consolidate the repeated 'See references/device-integrity-patterns.md for full...' pointers (the Common Patterns section ends with two back-to-back generic references, lines 370-373) into a single well-placed list of what lives in the reference file.

Define or annotate the undefined symbols in code examples (serverURL, currentAccountID, DeviceIntegrityError) — even a one-line note that they come from the Full Integration Manager in the reference file — so the Swift blocks are copy-paste ready.

Tighten the 'What the Two Bits Are For' section by moving the bit-semantics examples into the reference file, keeping only the persistence and reset facts inline.

DimensionReasoningScore

Conciseness

The body is efficient and sticks to non-obvious Apple-specific facts (two bits persist across reinstall, key-count risk metrics, extension-type support), but the generic pointer 'See references/device-integrity-patterns.md for full...' is repeated several times in quick succession (lines 338, 361, 370-373) and could be consolidated. Minor over-explanation keeps it below the lean anchor of 5.

4 / 5

Actionability

Complete, executable Swift code covers token generation, key generation with Keychain persistence, attestation, and attested requests — real API calls, not pseudocode. However, serverURL, currentAccountID, and DeviceIntegrityError are used but never defined in the main file, leaving minor gaps to copy-paste readiness.

4 / 5

Workflow Clarity

The three-phase flow (key generation, attestation, assertion) is explicitly sequenced up front, with validation gates ('Only treat the keyId as usable after your server verifies attestation'), error-driven feedback loops (retry .serverUnavailable with the same key/hash, discard and regenerate on other failures), and a 10-item review checklist. This matches the anchor for clear sequencing with explicit validation and error-recovery loops.

5 / 5

Progressive Disclosure

The SKILL.md is a clear client-side overview with well-signaled, one-level-deep references (references/device-integrity-patterns.md exists and contains every anchored section cited in the body). Server verification detail is appropriately split out, and a Contents list aids navigation.

5 / 5

Total

18

/

20

Passed

Description

92%Weight 40%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.

A strong description: specific, third-person, with a clear what and an explicit multi-scenario 'Use when...' clause. Only minor room to broaden natural trigger synonyms such as anti-fraud or tamper detection.

DimensionReasoningScore

Specificity

The description names the exact APIs (DCDevice, DCAppAttestService) and lists multiple concrete actions — 'per-device bits', 'key generation, attestation, and assertion flows' — covering the full scope of the skill. It matches the anchor for comprehensive coverage of specific concrete actions, not the level-4 anchor with minor gaps.

5 / 5

Completeness

The first sentence explicitly states what the skill does (verify device legitimacy and app integrity via DeviceCheck and App Attest), and the explicit 'Use when...' clause lists five concrete trigger scenarios. Both what and when are clearly answered with concrete trigger phrases.

5 / 5

Trigger Term Quality

Natural phrases users would say are present ('fraud prevention', 'detecting compromised devices', 'device verification', 'protecting sensitive API endpoints'), giving good keyword coverage. A few natural variations are missing (e.g., 'anti-fraud', 'tamper detection', 'bot detection'), so it falls just short of comprehensive synonym coverage.

4 / 5

Distinctiveness Conflict Risk

It occupies a clear niche (Apple DeviceCheck/App Attest on Apple platforms) with distinct triggers tied to Apple's servers and attested requests, so conflict risk with other skills is minimal.

5 / 5

Total

19

/

20

Passed

Validation

100%

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

dpearson2699/swift-ios-skills

Path

skills/device-integrity/SKILL.md

Reviewed

Table of Contents

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