CtrlK
BlogDocsLog inGet started
Tessl Logo

msn-js-sdk

Integrates the MSN JavaScript SDK (`window.$msstart`) into JavaScript games running on Microsoft Start. Handles SDK initialization, player authentication, cloud save key/value storage, display banner and interstitial/rewarded ad lifecycles, native sharing, leaderboard score submission, and in-app purchases. Use when the user mentions MSN SDK setup, MSN ads integration, game monetization with MSN, adding MSN features to a JavaScript game, `$msstart`, `msstart` script, MSN cloud save, or MSN IAP.

76

Quality

95%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide

SecuritybySnyk

Medium

Suggest reviewing before use

SKILL.md
Quality
Evals
Security

Quality

Content

90%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.

The body is a tight, executable reference for the MSN SDK with code for every feature and several genuinely non-obvious gotchas surfaced up front. Workflow sequencing and validation are present; the only gaps are explicit error-recovery feedback loops and some reference material that could be split out.

Suggestions

Add a validate→fix→retry feedback loop for the cloud-save round-trip (step 6) so a failed test data round-trip has a documented recovery path.

Consider extracting the IAP in-band failure-code catalog and the MSN_SIZES_BY_POSITION ad-size table into a separate reference file to keep the overview leaner.

Make the SDK version (rc.21) a single source of truth (define once and reuse) so a future version bump touches only one location.

DimensionReasoningScore

Conciseness

Lean and efficient: states only non-obvious constraints and gotchas (poll for the global, in-band IAP failure responses, whole-object cloud-save semantics) and provides executable code without explaining concepts Claude already knows like what a Promise or SDK is.

5 / 5

Actionability

Fully executable, copy-paste-ready code across every feature area (init, auth, cloud save, ads, share, leaderboards, IAP), with specific gotchas such as failure responses arriving in-band as `{ code: 'IAP_*_FAILURE' }` resolutions rather than rejections.

5 / 5

Workflow Clarity

A 6-step Integration Workflow with explicit gating, a 60-second interstitial timing constraint, and a validation step ('do a test getDataAsync round-trip before relying on cloud save'); falls short of 5 because validate→fix→retry feedback loops for recovery are largely absent.

4 / 5

Progressive Disclosure

Single-file with no bundle references, but well-organized under clear section headers and every section earns its place; slightly below 5 because the IAP failure-code behavior and ad-size reference table could optionally live in a separate reference file.

4 / 5

Total

18

/

20

Passed

Description

100%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.

The description is exemplary: it concisely enumerates concrete SDK capabilities and pairs them with an explicit, comprehensive 'Use when' trigger clause. It is third-person, specific, and avoids vague fluff or over-claims.

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions — 'SDK initialization, player authentication, cloud save key/value storage, display banner and interstitial/rewarded ad lifecycles, native sharing, leaderboard score submission, and in-app purchases' — giving comprehensive coverage of the SDK's capabilities.

5 / 5

Completeness

Explicitly answers both 'what' (enumerated SDK capabilities) and 'when' via a clear 'Use when the user mentions...' clause with concrete trigger phrases.

5 / 5

Trigger Term Quality

Comprehensive natural trigger terms including the API token `$msstart`, the `msstart` script name, and natural phrases like 'MSN SDK setup', 'MSN ads integration', 'game monetization with MSN', and 'MSN IAP' that a user would actually say.

5 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (MSN JavaScript SDK / Microsoft Start games) with distinct triggers (`$msstart`, `msstart`) that are unlikely to collide with other skills.

5 / 5

Total

20

/

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.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
popey/gamedev.sh-skills
Reviewed

Table of Contents

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.