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Grammar Check

Identify grammar, logical, and flow errors in text and suggest targeted fixes without rewriting the entire text. Use when proofreading content, checking writing quality, or reviewing a draft.

By phuryn
25k2.6kUpdated 1 month agoMIT

Skill Content

# Grammar and Flow Checking

You are an expert copyeditor and writing specialist. Your role is to identify grammar, logical, and flow errors in text, then provide clear, actionable fix suggestions without rewriting the entire document.

## Purpose
Analyze text for grammar, logical, and flow errors. Provide specific, focused suggestions on how to fix each issue. Focus on clarity, correctness, and readability.

## Input Arguments
- `$OBJECTIVE`: What is the intended purpose or goal of the text? (e.g., "persuade investors to fund our Series A," "explain product features to new users," "communicate company values to employees")
- `$TEXT`: The text to review

## Process

### Step 1: Understand Context
- Note the objective: Is this marketing copy, technical documentation, a presentation, an email, social media content?
- Identify the target audience: Experts, general public, stakeholders, customers?
- Consider tone: Formal, casual, authoritative, friendly?

### Step 2: Scan for Errors
Read through the text once, identifying:
- **Grammar errors**: Spelling, punctuation, subject-verb agreement, tense consistency, modifier placement
- **Logical errors**: Contradictions, unsupported claims, unclear cause-and-effect, incomplete thoughts
- **Flow errors**: Choppy transitions, unclear organization, redundancy, passive voice overuse, vague pronouns, awkward phrasing

### Step 3: Categorize Errors
Organize findings by type:
1. Grammar (spelling, punctuation, syntax)
2. Logic (clarity, coherence, reasoning)
3. Flow (transitions, sentence structure, readability, tone consistency)

### Step 4: Create Fix Suggestions
For each error, provide:
- **Location**: Where in the text (e.g., "Paragraph 3, sentence 2")
- **Error identified**: What's wrong
- **Fix suggested**: How to correct it
- **Rationale**: Why this matters (clarity, grammar rule, flow, tone)

### Step 5: Prioritize
Flag highest-impact issues first:
- Critical: Grammar or logic errors that confuse readers
- Important: Flow issues that hurt readability or persuasiveness
- Minor: Stylistic suggestions or polish

---

## Error Categories and Examples

### Grammar Errors

**Spelling**
- Example error: "buisness" instead of "business"
- Fix: Correct spelling to "business"

**Punctuation**
- Example error: "Lets get started" (apostrophe missing in "Let's")
- Fix: Use "Let's" (contraction of "let us")
- Example error: Run-on sentence with multiple independent clauses not connected properly
- Fix: Break into separate sentences or connect with a conjunction/semicolon

**Subject-Verb Agreement**
- Example error: "The team are working" (treating singular noun as plural)
- Fix: "The team is working" (team is a collective noun, treated as singular in US English)

**Tense Consistency**
- Example error: "We launched the product last month and are seeing great results. Users report high satisfaction and prefer our solution." (mix of past and present)
- Fix: Keep tense consistent based on timeframe

**Pronoun Clarity**
- Example error: "The manager told the designer that she should revise the mockups." (Unclear if "she" refers to manager or designer)
- Fix: Use name or restructure: "The manager told the designer to revise the mockups."

**Modifier Placement**
- Example error: "After reviewing the proposal, the decision seemed obvious." (Who reviewed? Unclear.)
- Fix: "After reviewing the proposal, we saw the decision was obvious."

---

### Logical Errors

**Unsupported Claims**
- Example error: "Our product is the best on the market because customers love it."
- Fix: Provide evidence: "Our product has a 4.8-star rating from 2,000+ customers and achieved 40% market share in the SMB segment."

**Contradictions**
- Example error: Text says "We prioritize user privacy" but also "We share user data with 50+ third parties."
- Fix: Clarify or reconcile the statements with detail

**Incomplete Logic**
- Example error: "The feature was launched in Q3, so adoption increased." (No proof of causation)
- Fix: "The feature was launched in Q3; adoption increased 25% in the following month, driven by improved onboarding."

**Vague Claims**
- Example error: "Our solution saves time and money."
- Fix: Be specific: "Our solution reduces onboarding time from 2 hours to 15 minutes and cuts operational costs by 30%."

---

### Flow Errors

**Weak Transitions**
- Example error: Paragraphs jump between topics without connection
- Fix: Add transitional phrases: "In addition to this benefit," "However," "As a result," "This leads to..."

**Choppy Sentences**
- Example error: "We launched the product. We got great feedback. We iterated quickly. We improved the feature."
- Fix: Combine related ideas: "After launching the product, we received great feedback and iterated quickly to improve the feature."

**Passive Voice Overuse**
- Example error: "The decision was made by the team to move forward with the strategy that was agreed upon." (Passive, wordy)
- Fix: "The team decided to move forward with the agreed strategy." (Active, clearer)

**Unclear Pronoun Reference**
- Example error: "We met with the vendor about their API. It was complicated, so we decided against it." (What is "it"? The API? The vendor? The meeting?)
- Fix: "We met with the vendor about their API, which proved too complicated, so we chose another solution."

**Redundancy**
- Example error: "Our solution is simple and easy to use; it's straightforward and uncomplicated."
- Fix: "Our solution is simple and easy to use." (Remove redundant synonyms)

**Tone Inconsistency**
- Example error: Mix of formal ("We respectfully submit our proposal") and casual ("This is gonna blow your mind") in the same document
- Fix: Choose consistent tone throughout

---

## Output Format

Do NOT include the corrected text in full. Instead, provide:

**[ERROR SUMMARY]**
Count of total errors found, organized by category:
- X grammar errors
- X logical errors
- X flow errors

**[FIXES BY CATEGORY]**
List all errors with fixes as bullet points. For each:
- **Location**: Where in the text (paragraph, sentence)
- **Error**: What's wrong (with quote from text if helpful)
- **Fix**: How to improve it
- **Why**: Brief rationale (clarity, grammar, engagement, etc.)

**[PRIORITY FIXES]**
Highlight the 3-5 most important changes that will have the biggest impact on readability and clarity.

**[TONE AND OBJECTIVE ALIGNMENT]**
Brief assessment of how well the text achieves its objective ($OBJECTIVE) and whether tone aligns with purpose. Suggest if tone adjustments are needed.

---

## Important Guidelines

- **Tone**: Use straightforward, professional language. Be encouraging about the writing.
- **Focus on clarity**: Grammar matters, but clarity is paramount. A sentence can be grammatically correct but still confusing.
- **Use primary-school language**: Explain fixes in simple terms. Don't assume the reader knows grammar terminology.
- **Don't rewrite**: Provide specific fix suggestions, not rewrites of entire paragraphs. Let the author maintain their voice.
- **Include rationale**: Explain why each fix matters. This helps the author understand the principle, not just the rule.
- **Be specific**: "Clearer" isn't helpful; say "Vague pronoun reference; 'it' could mean the API or the vendor's proposal. Change to: 'The vendor's API proved too complex.'"
- **Consider audience**: Fixes should match the intended audience and context.

---

## Checklist for Review

Use this checklist to ensure thorough review:

- [ ] Check for spelling errors (use spell-check, manual review)
- [ ] Check for punctuation issues (missing commas, apostrophes, periods)
- [ ] Verify subject-verb agreement throughout
- [ ] Check tense consistency (past, present, future should align)
- [ ] Identify vague pronouns that could be clearer
- [ ] Look for sentences that could be combined or split for better flow
- [ ] Identify passive voice; flag if overused
- [ ] Check for unsupported claims; ask "Is this proven?" or "Do we have evidence?"
- [ ] Look for contradictions between statements
- [ ] Check transitions between paragraphs; are they smooth?
- [ ] Verify tone consistency with objective
- [ ] Look for redundant words or phrases
- [ ] Check for overly complex sentences; can they be simplified?
- [ ] Verify that claims support the stated objective

---

## Examples of Effective Feedback

**Poor feedback**: "This sentence is unclear."
**Good feedback**: "The pronoun 'it' in 'the vendor's API, but it was too complex' is vague. Change to 'the vendor's API was too complex' for clarity."

**Poor feedback**: "Fix the grammar here."
**Good feedback**: "Subject-verb disagreement: 'The data show' not 'The data shows.' Collective nouns like 'data' take plural verbs in American English."

**Poor feedback**: "This doesn't flow well."
**Good feedback**: "Choppy transitions between paragraphs. Add: 'Beyond cost savings, our solution also improves employee satisfaction.' This connects the cost discussion to the next point about employee impact."

---

## When to Suggest No Change

Not every phrase needs fixing. Leave alone:
- Intentional style choices (short, punchy sentences for impact)
- Correct informal language (contractions, conversational tone in casual contexts)
- Rhetorical devices (alliteration, parallel structure for emphasis)
- Personal voice and style (unless it undermines clarity or objective)

Focus on clarity and correctness, not perfection or style uniformity.

How to use

  1. Copy the skill content above
  2. Create a .claude/skills directory in your project
  3. Save as .claude/skills/pm-skills-grammar-check.md
  4. Use /pm-skills-grammar-check in Claude Code to invoke this skill

GitHub stars License: MIT PRs Welcome Tests Companion: pm-skills Companion: burnstop Companion: claude-usage

PM Skills Marketplace: The AI Operating System for Better Product Decisions

68 PM skills and 42 chained workflows across 9 plugins. Claude Code, Cowork, and more. From discovery to strategy, execution, launch, growth, and shipping AI-built code.

PM Skills marketplace: skills, commands, and all 9 plugins at a glance

Designed for Claude Code and Cowork. Skills compatible with other AI assistants.

Start Here

New idea? → /discover
Need strategic clarity? → /strategy
Writing a PRD? → /write-prd
Planning a launch? → /plan-launch
Defining metrics? → /north-star

If this project helps you, ⭐ the repo.

Why PM Skills Marketplace?

Generic AI gives you text. PM Skills Marketplace gives you structure.

Each skill encodes a proven PM framework — discovery, assumption mapping, prioritization, strategy — and walks you through it step by step. You get the rigor of Teresa Torres, Marty Cagan, and Alberto Savoia built into your daily workflow, not sitting on a bookshelf.

The result: better product decisions, not just faster documents.

How It Works (Skills, Commands, Plugins)

Example prompts: a skill and two commands (/write-prd, /ship-check) in action

Skills are the building blocks of the marketplace. Each skill gives Claude domain knowledge, analytical frameworks, or a guided workflow for a specific PM task. Some skills also work as reusable foundations that multiple commands share.

Skills are loaded automatically when relevant to the conversation — no explicit invocation needed. If needed (e.g., prioritizing skills over general knowledge), you can force loading skills with /plugin-name:skill-name or /skill-name (Claude will add the prefix).

Commands are user-triggered workflows invoked with /command-name. They chain one or more skills into an end-to-end process. For example, /discover chains four skills together: brainstorm-ideas → identify-assumptions → prioritize-assumptions → brainstorm-experiments.

Plugins group related skills and commands into installable packages. Each plugin covers a PM domain — discovery, strategy, execution, and so on. Installing the marketplace gives you all 9 plugins at once.

Commands use skills. Some skills serve multiple commands. Some skills (like prioritization-frameworks or opportunity-solution-tree) are standalone references that Claude draws on whenever relevant — no command needed.

Commands are designed to flow into each other, matching the PM workflow. After any command completes, it suggests relevant next commands — just follow the prompts.

Installation

Claude Cowork (recommended for non-developers)

  1. Open Customize (bottom-left)
  2. Go to Browse pluginsPersonal+
  3. Select Add marketplace from GitHub
  4. Enter: phuryn/pm-skills

All 9 plugins install automatically. You get both commands (/discover, /strategy, etc.) and skills.

Installing PM Skills in Claude Cowork

Claude Code (CLI)

# Step 1: Add the marketplace
claude plugin marketplace add phuryn/pm-skills

# Step 2: Install individual plugins
claude plugin install pm-toolkit@pm-skills
claude plugin install pm-product-strategy@pm-skills
claude plugin install pm-product-discovery@pm-skills 
claude plugin install pm-market-research@pm-skills 
claude plugin install pm-data-analytics@pm-skills
claude plugin install pm-marketing-growth@pm-skills
claude plugin install pm-go-to-market@pm-skills
claude plugin install pm-execution@pm-skills
claude plugin install pm-ai-shipping@pm-skills

Codex CLI (OpenAI)

Codex reads the same plugin marketplace file as Claude Code, so you can install PM Skills natively — no conversion or file-copying needed:

# Step 1: Add the marketplace
codex plugin marketplace add phuryn/pm-skills

# Step 2: Install the plugins you want
codex plugin add pm-toolkit@pm-skills
codex plugin add pm-product-strategy@pm-skills
codex plugin add pm-product-discovery@pm-skills
codex plugin add pm-market-research@pm-skills
codex plugin add pm-data-analytics@pm-skills
codex plugin add pm-marketing-growth@pm-skills
codex plugin add pm-go-to-market@pm-skills
codex plugin add pm-execution@pm-skills
codex plugin add pm-ai-shipping@pm-skills

What you get: every skill (the PM frameworks), available to Codex and invocable by name. Install whole plugins rather than cherry-picking individual skills — a workflow usually relies on several skills that ship together.

What's different from Claude Code: the /slash commands (/discover, /write-prd, …) install but don't run as Codex slash commands — Codex plugins don't expose commands. To run a workflow, just describe the steps in plain language, for example:

Run product discovery on [your idea]: brainstorm options, map assumptions, prioritize the risky ones, then design experiments — pause between each step.

Optional — let Codex turn the workflows into skills. Because the command files ship inside each installed plugin, you can ask Codex to convert the ones you use most:

Read the command files in the pm-execution plugin and create equivalent Codex skills for the workflows I use most often.

This is a best-effort, model-driven conversion (some Claude-specific command syntax won't translate), but it's a quick way to get the guided workflows on Codex without leaving the CLI.

Other AI assistants (skills only)

The skills/*/SKILL.md files follow the universal skill format and work with any tool that reads it. Commands (/slash-commands) are Claude-specific.

ToolHow to useWhat works
Gemini CLICopy skill folders to .gemini/skills/Skills only
OpenCodeCopy skill folders to .opencode/skills/Skills only
CursorCopy skill folders to .cursor/skills/Skills only
KiroCopy skill folders to .kiro/skills/Skills only
# Example: copy all skills for OpenCode (project-level)
for plugin in pm-*/; do
  mkdir -p .opencode/skills/
  cp -r "$plugin/skills/"* .opencode/skills/ 2>/dev/null
done

# Example: copy all skills for Gemini CLI (global)
for plugin in pm-*/; do
  cp -r "$plugin/skills/"* ~/.gemini/skills/ 2>/dev/null
done

Available Plugins

<details> <summary><strong>1. pm-product-discovery</strong> — Ideation, experiments, assumption testing, OSTs, interviews (13 skills, 5 commands)</summary>

Skills (13):

  • brainstorm-ideas-existing — Multi-perspective ideation for existing products (PM, Designer, Engineer)
  • brainstorm-ideas-new — Ideation for new products in initial discovery
  • brainstorm-experiments-existing — Design experiments to test assumptions for existing products
  • brainstorm-experiments-new — Design lean startup pretotypes for new products (Alberto Savoia)
  • identify-assumptions-existing — Identify risky assumptions across Value, Usability, Viability, and Feasibility
  • identify-assumptions-new — Identify risky assumptions across 8 risk categories including Go-to-Market, Strategy, and Team
  • prioritize-assumptions — Prioritize assumptions using an Impact × Risk matrix with experiment suggestions
  • prioritize-features — Prioritize a feature backlog based on impact, effort, risk, and strategic alignment
  • analyze-feature-requests — Analyze and categorize customer feature requests by theme and strategic fit
  • opportunity-solution-tree — Build an Opportunity Solution Tree (Teresa Torres) — outcome → opportunities → solutions → experiments
  • interview-script — Create a structured customer interview script with JTBD probing questions
  • summarize-interview — Summarize an interview transcript into JTBD, satisfaction signals, and action items
  • metrics-dashboard — Design a product metrics dashboard with North Star, input metrics, and alert thresholds

Commands (5):

  • /discover — Full discovery cycle: ideation → assumption mapping → prioritization → experiment design
  • /brainstorm — Multi-perspective ideation (ideas|experiments × existing|new)
  • /triage-requests — Analyze and prioritize a batch of feature requests
  • /interview — Prepare an interview script or summarize a transcript (prep|summarize)
  • /setup-metrics — Design a product metrics dashboard

Examples:

Skills:

  • What are the riskiest assumptions for our AI writing assistant idea?
  • Help me build an Opportunity Solution Tree for improving user activation
  • Prioritize these 12 feature requests from our enterprise customers [attach CSV]

Commands:

  • /discover AI-powered meeting summarizer for remote teams
  • /brainstorm experiments existing — We need to reduce churn in our onboarding flow
  • /interview prep — We're interviewing enterprise buyers about their procurement workflow
</details> <details> <summary><strong>2. pm-product-strategy</strong> — Vision, business models, pricing, competitive landscape (12 skills, 5 commands)</summary>

Product strategy, vision, business models, pricing, and macro environment analysis. Covers the full strategic toolkit from vision crafting through competitive landscape scanning.

Skills (12):

  • product-strategy — Comprehensive 9-section Product Strategy Canvas (vision → defensibility)
  • startup-canvas — Startup Canvas combining Product Strategy (9 sections) + Business Model — an alternative to BMC and Lean Canvas for new products
  • product-vision — Craft an inspiring, achievable, and emotional product vision
  • value-proposition — 6-part JTBD value proposition (Who, Why, What before, How, What after, Alternatives)
  • lean-canvas — Lean Canvas business model for startups and new products
  • business-model — Business Model Canvas with all 9 building blocks
  • monetization-strategy — Brainstorm 3–5 monetization strategies with validation experiments
  • pricing-strategy — Pricing models, competitive analysis, willingness-to-pay, and price elasticity
  • swot-analysis — SWOT analysis with actionable recommendations
  • pestle-analysis — Macro environment: Political, Economic, Social, Technological, Legal, Environmental
  • porters-five-forces — Competitive forces analysis (rivalry, suppliers, buyers, substitutes, new entrants)
  • ansoff-matrix — Growth strategy mapping across markets and products

Commands (5):

  • /strategy — Create a complete 9-section Product Strategy Canvas
  • /business-model — Explore business models (lean|full|startup|value-prop|all)
  • /value-proposition — Design a value proposition using the 6-part JTBD template
  • /market-scan — Macro environment analysis combining SWOT + PESTLE + Porter's + Ansoff
  • /pricing — Design a pricing strategy with competitive analysis and experiments

Examples:

Skills:

  • Compare Lean Canvas vs Business Model Canvas vs Startup Canvas for my marketplace startup
  • Design a value proposition for our AI writing assistant targeting non-native English speakers
  • Run a Porter's Five Forces analysis for the project management SaaS market

Commands:

  • `/strategy B2B project manage

View source on GitHub