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kevin-ryan-io/spec-driven-development

A practitioner methodology for AI-native software engineering where specifications are the primary artifact and code is a generated side effect.

93

Quality

93%

Does it follow best practices?

Impact

Pending

No eval scenarios have been run

Overview
Skills
Evals
Files

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 strong, well-crafted skill description that excels across all dimensions. It provides specific concrete actions, comprehensive trigger terms including both natural language scenarios and domain-specific keywords, explicit 'Use when...' guidance, and a distinctive niche that clearly separates it from general coding or documentation skills.

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: 'Creates structured specifications', 'validates execution plans against specs', 'manages two-loop planning-to-execution workflows with decision gates', and 'captures provenance of AI-generated work'.

3 / 3

Completeness

Clearly answers both what (creates specs, validates plans, manages workflows, captures provenance) AND when with explicit 'Use when...' clause covering multiple trigger scenarios including problem-based triggers ('agent keeps building the wrong thing') and keyword triggers.

3 / 3

Trigger Term Quality

Excellent coverage of natural terms users would say: 'spec-driven', 'SDD', 'specification first', 'code is a side effect', 'agent keeps building the wrong thing', 'decision gates', 'provenance', 'AI coding agents', 'non-trivial feature'.

3 / 3

Distinctiveness Conflict Risk

Clear niche focused on spec-driven development with AI agents, two-loop workflows, and decision gates. The specific terminology ('SDD', 'spec-driven', 'provenance', 'two-loop') creates distinct triggers unlikely to conflict with general coding or documentation skills.

3 / 3

Total

12

/

12

Passed

Implementation

85%

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

This is a strong skill document that clearly teaches a complex two-loop workflow with explicit decision gates and validation checkpoints. The actionability and workflow clarity are excellent, with concrete steps and clear branching logic. Minor verbosity in philosophical framing prevents a perfect conciseness score, but the content earns its length through genuine instructional value.

DimensionReasoningScore

Conciseness

The content is well-written but includes some philosophical framing ('Code is a generated side effect', 'Cognitive budget replaces developer-hours') that, while valuable for understanding, adds tokens beyond pure instruction. The core workflow could be tighter.

2 / 3

Actionability

Provides concrete, numbered steps for both loops, explicit spec format with required sections, clear decision gate criteria, and specific guidance like 'three prompts' for execution. The spec template sections are copy-paste ready.

3 / 3

Workflow Clarity

Excellent workflow structure with nine clearly numbered steps across two loops, an explicit decision gate at step 6 with clear branching logic (fix spec vs fix plan), and mandatory validation checkpoints. The 'When NOT to Use SDD' section adds appropriate boundaries.

3 / 3

Progressive Disclosure

Well-structured with clear overview sections and appropriate references to external files (references/principles.md, references/anti-patterns.md) for detailed content. The main document stays focused on the workflow while pointing to deeper material.

3 / 3

Total

11

/

12

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.

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Install with Tessl CLI

npx tessl i kevin-ryan-io/spec-driven-development@1.1.0

Reviewed

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