Spec Kit Specify Skill

When to Use

The user wants a new or updated feature spec from a natural language description.

Inputs

Feature description from the user.

Repo context with

.specify/

scripts and templates.

If the description is missing or unclear, ask a targeted question before continuing.

Workflow

The user's feature description in the request

is

the input. Do not ask them to repeat it unless it is missing.

Given that feature description, do this:

Generate a concise short name

(2-4 words) for the branch:

Analyze the feature description and extract the most meaningful keywords

Create a 2-4 word short name that captures the essence of the feature

Use action-noun format when possible (e.g., "add-user-auth", "fix-payment-bug")

Preserve technical terms and acronyms (OAuth2, API, JWT, etc.)

Keep it concise but descriptive enough to understand the feature at a glance

Examples:

"I want to add user authentication" → "user-auth"

"Implement OAuth2 integration for the API" → "oauth2-api-integration"

"Create a dashboard for analytics" → "analytics-dashboard"

"Fix payment processing timeout bug" → "fix-payment-timeout"

Check for existing branches before creating new one

:

a. First, fetch all remote branches to ensure we have the latest information:

git

fetch

--all

--prune

b. Find the highest feature number across all sources for the short-name:

Remote branches:

git ls-remote --heads origin | grep -E 'refs/heads/[0-9]+-$'

Local branches:

git branch | grep -E '^[ ][0-9]+-$'

Specs directories: Check for directories matching

specs/[0-9]+-

c. Determine the next available number:

Extract all numbers from all three sources

Find the highest number N

Use N+1 for the new branch number

d. Run the script

.specify/scripts/bash/create-new-feature.sh --json ""

with the calculated number and short-name:

Pass

--number N+1

and

--short-name "your-short-name"

along with the feature description

Bash example:

.specify/scripts/bash/create-new-feature.sh --json --number 5 --short-name "user-auth" "Add user authentication"

PowerShell example:

.specify/scripts/bash/create-new-feature.sh -Json -Number 5 -ShortName "user-auth" "Add user authentication"

IMPORTANT

:

Check all three sources (remote branches, local branches, specs directories) to find the highest number

Only match branches/directories with the exact short-name pattern

If no existing branches/directories found with this short-name, start with number 1

You must only ever run this script once per feature

The JSON is provided in the terminal as output - always refer to it to get the actual content you're looking for

The JSON output will contain BRANCH_NAME and SPEC_FILE paths

For single quotes in args like "I'm Groot", use escape syntax: e.g 'I'''m Groot' (or double-quote if possible: "I'm Groot")

Load

.specify/templates/spec-template.md

to understand required sections.

Follow this execution flow:

Parse user description from Input

If empty: ERROR "No feature description provided"

Extract key concepts from description

Identify: actors, actions, data, constraints

For unclear aspects:

Make informed guesses based on context and industry standards

Only mark with [NEEDS CLARIFICATION: specific question] if:

The choice significantly impacts feature scope or user experience

Multiple reasonable interpretations exist with different implications

No reasonable default exists

LIMIT: Maximum 3 [NEEDS CLARIFICATION] markers total

Prioritize clarifications by impact: scope > security/privacy > user experience > technical details

Fill User Scenarios & Testing section

If no clear user flow: ERROR "Cannot determine user scenarios"

Generate Functional Requirements

Each requirement must be testable

Use reasonable defaults for unspecified details (document assumptions in Assumptions section)

Define Success Criteria

Create measurable, technology-agnostic outcomes

Include both quantitative metrics (time, performance, volume) and qualitative measures (user satisfaction, task completion)

Each criterion must be verifiable without implementation details

Identify Key Entities (if data involved)

Return: SUCCESS (spec ready for planning)

Write the specification to SPEC_FILE using the template structure, replacing placeholders with concrete details derived from the feature description (arguments) while preserving section order and headings.

Specification Quality Validation

After writing the initial spec, validate it against quality criteria:

a.

Create Spec Quality Checklist

Generate a checklist file at FEATURE_DIR/checklists/requirements.md using the checklist template structure with these validation items:

Specification Quality Checklist: [FEATURE NAME]

**

Purpose

**

Validate specification completeness and quality before proceeding to planning

**

Created

**

[DATE]

**

Feature

**

[Link to spec.md]

Content Quality

[ ] No implementation details (languages, frameworks, APIs)

[ ] Focused on user value and business needs

[ ] Written for non-technical stakeholders

[ ] All mandatory sections completed

Requirement Completeness

[ ] No [NEEDS CLARIFICATION] markers remain

[ ] Requirements are testable and unambiguous

[ ] Success criteria are measurable

[ ] Success criteria are technology-agnostic (no implementation details)

[ ] All acceptance scenarios are defined

[ ] Edge cases are identified

[ ] Scope is clearly bounded

[ ] Dependencies and assumptions identified

Feature Readiness

[ ] All functional requirements have clear acceptance criteria

[ ] User scenarios cover primary flows

[ ] Feature meets measurable outcomes defined in Success Criteria

[ ] No implementation details leak into specification

Notes

Items marked incomplete require spec updates before the speckit-clarify or speckit-plan skills

b.

Run Validation Check

Review the spec against each checklist item:

For each item, determine if it passes or fails

Document specific issues found (quote relevant spec sections)

c.

Handle Validation Results

:

If all items pass

Mark checklist complete and proceed to step 6

If items fail (excluding [NEEDS CLARIFICATION])

:

List the failing items and specific issues

Update the spec to address each issue

Re-run validation until all items pass (max 3 iterations)

If still failing after 3 iterations, document remaining issues in checklist notes and warn user

If [NEEDS CLARIFICATION] markers remain

:

Extract all [NEEDS CLARIFICATION: ...] markers from the spec

LIMIT CHECK

If more than 3 markers exist, keep only the 3 most critical (by scope/security/UX impact) and make informed guesses for the rest For each clarification needed (max 3), present options to user in this format:

Question [N]: [Topic]

**

Context

**

[Quote relevant spec section]

**

What we need to know

**

[Specific question from NEEDS CLARIFICATION marker] ** Suggested Answers ** : | Option | Answer | Implications | |

|

|

|

|

A

|

[First suggested answer]

|

[What this means for the feature]

|

|

B

|

[Second suggested answer]

|

[What this means for the feature]

|

|

C

|

[Third suggested answer]

|

[What this means for the feature]

|

|

Custom

|

Provide your own answer

|

[Explain how to provide custom input]

|

**

Your choice

**

:

_

[Wait for user response]

_

CRITICAL - Table Formatting

Ensure markdown tables are properly formatted:

Use consistent spacing with pipes aligned

Each cell should have spaces around content:

| Content |

not

|Content|

Header separator must have at least 3 dashes:

|--------|

Test that the table renders correctly in markdown preview

Number questions sequentially (Q1, Q2, Q3 - max 3 total)

Present all questions together before waiting for responses

Wait for user to respond with their choices for all questions (e.g., "Q1: A, Q2: Custom - [details], Q3: B")

Update the spec by replacing each [NEEDS CLARIFICATION] marker with the user's selected or provided answer

Re-run validation after all clarifications are resolved

d.

Update Checklist

After each validation iteration, update the checklist file with current pass/fail status

Report completion with branch name, spec file path, checklist results, and readiness for the next phase (speckit-clarify or speckit-plan).

NOTE:

The script creates and checks out the new branch and initializes the spec file before writing.

Outputs

specs//spec.md

specs//checklists/requirements.md

New feature branch created by

.specify/scripts/bash/create-new-feature.sh

Next Steps

After generating the spec:

Clarify

requirements with speckit-clarify.

Plan

implementation with speckit-plan.

General Guidelines

Quick Guidelines

Focus on

WHAT

users need and

WHY

.

Avoid HOW to implement (no tech stack, APIs, code structure).

Written for business stakeholders, not developers.

DO NOT create any checklists that are embedded in the spec. That will be a separate skill.

Section Requirements

Mandatory sections

Must be completed for every feature

Optional sections

Include only when relevant to the feature

When a section doesn't apply, remove it entirely (don't leave as "N/A")

For AI Generation

When creating this spec from a user prompt:

Make informed guesses

Use context, industry standards, and common patterns to fill gaps

Document assumptions

Record reasonable defaults in the Assumptions section

Limit clarifications

Maximum 3 [NEEDS CLARIFICATION] markers - use only for critical decisions that:

Significantly impact feature scope or user experience

Have multiple reasonable interpretations with different implications

Lack any reasonable default

Prioritize clarifications

scope > security/privacy > user experience > technical details

Think like a tester

Every vague requirement should fail the "testable and unambiguous" checklist item

Common areas needing clarification

(only if no reasonable default exists):

Feature scope and boundaries (include/exclude specific use cases)

User types and permissions (if multiple conflicting interpretations possible)

Security/compliance requirements (when legally/financially significant)

Examples of reasonable defaults

(don't ask about these):

Data retention: Industry-standard practices for the domain

Performance targets: Standard web/mobile app expectations unless specified

Error handling: User-friendly messages with appropriate fallbacks

Authentication method: Standard session-based or OAuth2 for web apps

Integration patterns: RESTful APIs unless specified otherwise

Success Criteria Guidelines

Success criteria must be:

Measurable

Include specific metrics (time, percentage, count, rate)

Technology-agnostic

No mention of frameworks, languages, databases, or tools

User-focused

Describe outcomes from user/business perspective, not system internals

Verifiable

Can be tested/validated without knowing implementation details Good examples : "Users can complete checkout in under 3 minutes" "System supports 10,000 concurrent users" "95% of searches return results in under 1 second" "Task completion rate improves by 40%" Bad examples (implementation-focused): "API response time is under 200ms" (too technical, use "Users see results instantly") "Database can handle 1000 TPS" (implementation detail, use user-facing metric) "React components render efficiently" (framework-specific) "Redis cache hit rate above 80%" (technology-specific)