Creates Rails concerns for shared behavior across models or controllers with TDD. Use when extracting shared code, creating reusable modules, DRYing up models/controllers, or when user mentions concerns, modules, mixins, or shared behavior.
Install with Tessl CLI
npx tessl i github:ThibautBaissac/rails_ai_agents --skill rails-concern90
Does it follow best practices?
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npx tessl skill review --optimize ./path/to/skillAgent success when using this skill
Validation for skill structure
Discovery
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 excels across all dimensions. It uses proper third-person voice, provides specific concrete actions, includes comprehensive trigger terms that Rails developers would naturally use, and has an explicit 'Use when...' clause with clear guidance. The description effectively distinguishes itself from general Ruby or coding skills.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists specific concrete actions: 'Creates Rails concerns', 'shared behavior across models or controllers', 'with TDD', 'extracting shared code', 'creating reusable modules', 'DRYing up models/controllers'. Multiple specific actions are clearly stated. | 3 / 3 |
Completeness | Clearly answers both what ('Creates Rails concerns for shared behavior across models or controllers with TDD') and when ('Use when extracting shared code, creating reusable modules, DRYing up models/controllers, or when user mentions concerns, modules, mixins, or shared behavior'). | 3 / 3 |
Trigger Term Quality | Excellent coverage of natural terms users would say: 'concerns', 'modules', 'mixins', 'shared behavior', 'DRYing up', 'models/controllers', 'reusable modules', 'extracting shared code'. These are terms Rails developers naturally use. | 3 / 3 |
Distinctiveness Conflict Risk | Highly specific to Rails concerns with clear niche. The combination of 'Rails concerns', 'TDD', 'mixins', and 'shared behavior' creates distinct triggers unlikely to conflict with general Ruby or other framework skills. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
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 solid, actionable skill with excellent TDD workflow clarity and executable code examples. The main weakness is verbosity - it includes more patterns than necessary and some explanatory content about when to use concerns that experienced Rails developers wouldn't need. The content would benefit from splitting detailed patterns into a separate reference file.
Suggestions
Reduce the 'Common Concern Patterns' section to 2-3 essential patterns and move the rest to a separate PATTERNS.md file
Trim or remove the 'When to Use Concerns' section - Rails developers know when to use concerns
Remove the checklist at the end as it largely duplicates the workflow steps
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The skill is reasonably efficient but includes some redundancy - multiple similar concern patterns (5 patterns) when 2-3 would suffice, and the 'When to Use Concerns' section explains concepts Rails developers already know. The checklist at the end repeats information from the workflow. | 2 / 3 |
Actionability | Excellent actionability with fully executable, copy-paste ready code examples throughout. Every pattern includes complete, working Ruby code with proper module structure, and the TDD workflow provides concrete spec examples that can be directly used. | 3 / 3 |
Workflow Clarity | Clear 4-step TDD workflow (RED-GREEN) with explicit validation checkpoints - 'Run spec to confirm RED' and 'Run spec to confirm GREEN'. The workflow includes specific bash commands for running specs and a feedback loop for the TDD cycle. | 3 / 3 |
Progressive Disclosure | Content is well-structured with clear sections, but everything is in one monolithic file. The 5 common patterns section could be split into a separate PATTERNS.md file, and the controller vs model concern examples could benefit from separate reference files for complex use cases. | 2 / 3 |
Total | 10 / 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.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
allowed_tools_field | 'allowed-tools' contains unusual tool name(s) | Warning |
Total | 10 / 11 Passed | |
Table of Contents
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