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sinch-partnerships-ecosystems/sinch-skills

Official Sinch API skills for AI coding agents — SMS, Voice, Verification, Numbers, Mailgun email, and more.

71

Quality

88%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

This plugin was archived by the owner on Jun 4, 2026

Reason: we moved this to another workspace

Overview
Quality
Evals
Security
Files

Quality

Content

77%

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

This is a well-crafted skill that provides highly actionable, concrete guidance for using the Mailgun Inspect API. Its strongest aspects are the clear async workflow with explicit validation checkpoints and the executable curl examples. The main weakness is moderate redundancy — key concepts like async polling and credential handling are repeated across multiple sections — and the document is somewhat long for a SKILL.md overview, though the content density is generally justified.

Suggestions

Consolidate the async polling guidance into a single authoritative section and reference it elsewhere, rather than restating it in Agent Instructions, Async Workflow, Response Lifecycle, and Gotchas.

Remove or significantly trim the credential handling advice ('never hardcode API keys', 'do not paste live keys') — Claude already understands security best practices and this adds ~10 lines of low-value content.

DimensionReasoningScore

Conciseness

Generally efficient but has some redundancy — the async polling requirement is stated in at least three places (Agent Instructions, Async Workflow section, Gotchas), and some explanations like 'Store credentials in environment variables — never hardcode API keys' are things Claude already knows. The capability table and gotchas are well-structured, but the overall document could be tightened by ~20%.

2 / 3

Actionability

Provides fully executable curl commands with proper auth headers, specific endpoint paths, concrete JSON request bodies, and clear parameter values. The canonical example is copy-paste ready, and the common patterns section gives specific endpoint paths and body formats for each capability.

3 / 3

Workflow Clarity

The async create-then-poll workflow is clearly sequenced with explicit validation checkpoints (poll until 'Complete'/'Completed', treat 'Failed' as terminal error). The full pre-send check pattern provides a clear 5-step sequence, and the agent instructions give a decision tree for routing user requests. Error recovery is addressed via the polling loop.

3 / 3

Progressive Disclosure

References to 'references/api-endpoints.md' and '../sinch-authentication/SKILL.md' are well-signaled and one level deep, which is good. However, no bundle files were provided to verify these references exist, and the SKILL.md itself is quite long (~180 lines of content) with some sections (like the full gotchas list and links section) that could potentially be split out. The structure is reasonable but the main file carries a lot of inline detail.

2 / 3

Total

10

/

12

Passed

Description

100%

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

This is a well-crafted skill description that clearly communicates what the skill does (email quality checking via Mailgun Inspect API) and when to use it (with explicit trigger scenarios). It uses third-person voice, includes natural trigger terms, and occupies a distinct niche that minimizes conflict risk with other skills.

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: checking email quality, previewing across clients, checking accessibility (WCAG), validating links, validating images, and analyzing HTML/CSS compatibility.

3 / 3

Completeness

Clearly answers both 'what' (checks email quality via Mailgun Inspect API) and 'when' with an explicit 'Use when...' clause listing specific trigger scenarios like previewing emails, checking accessibility, validating links/images, and analyzing compatibility.

3 / 3

Trigger Term Quality

Includes strong natural trigger terms users would say: 'email quality', 'previewing emails', 'accessibility', 'WCAG', 'validating links', 'validating images', 'email HTML/CSS compatibility', 'Mailgun'. Good coverage of variations a user might mention.

3 / 3

Distinctiveness Conflict Risk

Highly distinctive with a clear niche: email quality checking via a specific API (Mailgun Inspect). The combination of email previewing, WCAG accessibility, link/image validation, and HTML/CSS compatibility creates a unique profile unlikely to conflict with other skills.

3 / 3

Total

12

/

12

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

metadata_field

'metadata' should map string keys to string values

Warning

Total

10

/

11

Passed

Reviewed

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