How do I install the Email Character Count skill?

Run npx skillmds@latest add dx-architecture/email-character-count in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Email Character Count safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Email Character Count?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Email Character Count free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Email Character Count?

DX-Architecture (@dx-architecture) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Email Character Count by dx-architecture

Name: Email Character Count
Author: DX-Architecture

Email Character Count

Checks email copy character counts against section limits (subject line, preheader, H1, H2, H3, body, CTA, secondary CTA). Use only when the user explicitly asks to check email length, character counts, subject line, preheader, or these section guidelines.

File contents

Email character count

Count characters in each provided section and compare them to these limits.

Limits

Section	Limit	Required
Subject Line	40	yes
Preheader	50	yes
H1 (optional)	35	no
H2 (optional)	40	no
H3 (optional)	35	no
Body	500	yes
CTA	25	yes
Secondary CTA (optional)	200	no

Use these values exactly. Do not substitute industry averages.

Field aliases

Map copy-doc labels to skill sections when needed:

Copy-doc label	Section
Subject line	Subject Line
Preview text	Preheader
Hero/banner heading	H1
Hero – Title	H2
Body copy	Body
CTA button copy	CTA
Secondary CTA	Secondary CTA

How to count

Count every character, including spaces and punctuation.
Trim leading and trailing whitespace first; do not count it.
Do not count the section label (Subject Line:, H1:, etc.).
Skip optional sections that are missing or empty. Do not fail them.
Fail a required section if it is missing or empty.

Workflow

Extract the copy for each section the user provided.
Run the checker (preferred), from this repository root:

python3 .cursor/skills/email-character-count/scripts/check_counts.py path/to/copy.txt

Or pass JSON:

python3 .cursor/skills/email-character-count/scripts/check_counts.py --json '{"Subject Line":"...","Preheader":"...","Body":"...","CTA":"..."}'

From the skill folder, use python3 scripts/check_counts.py instead.

If the script cannot run, count manually with the same rules and the same output format.
Report results. Do not rewrite copy unless the user asks.

Output

Use this table, then a one-line pass/fail summary:

| Section | Count | Limit | Status |
|---|---|---|---|
| Subject Line | 38 | 40 | Pass |
| Preheader | 52 | 50 | Fail (2 over) |

Status values:

Pass — count is within the limit
Fail (N over) — count exceeds the limit
Fail (missing) — required section is empty
Skipped — optional section not provided

Overall: Pass only if every required section passes and every provided optional section passes.

Input format

Accept labeled copy like this:

Subject Line: ...
Preheader: ...
H1: ...
H2: ...
H3: ...
Body: ...
CTA: ...
Secondary CTA: ...

Optional headings may be omitted. Body may be multiple lines until the next section label.

---name: email-character-countdescription: Checks email copy character counts against section limits (subject line, preheader, H1, H2, H3, body, CTA, secondary CTA). Use only when the user explicitly asks to check email length, character counts, subject line, preheader, or these section guidelines.---# Email character countCount characters in each provided section and compare them to these limits.## Limits| Section | Limit | Required ||---|---|---|| Subject Line | 40 | yes || Preheader | 50 | yes || H1 (optional) | 35 | no || H2 (optional) | 40 | no || H3 (optional) | 35 | no || Body | 500 | yes || CTA | 25 | yes || Secondary CTA (optional) | 200 | no |Use these values exactly. Do not substitute industry averages.## Field aliasesMap copy-doc labels to skill sections when needed:| Copy-doc label | Section ||---|---|| Subject line | Subject Line || Preview text | Preheader || Hero/banner heading | H1 || Hero – Title | H2 || Body copy | Body || CTA button copy | CTA || Secondary CTA | Secondary CTA |## How to count- Count every character, including spaces and punctuation.- Trim leading and trailing whitespace first; do not count it.- Do not count the section label (`Subject Line:`, `H1:`, etc.).- Skip optional sections that are missing or empty. Do not fail them.- Fail a required section if it is missing or empty.## Workflow1. Extract the copy for each section the user provided.2. Run the checker (preferred), from this repository root:```bashpython3 .cursor/skills/email-character-count/scripts/check_counts.py path/to/copy.txt```Or pass JSON:```bashpython3 .cursor/skills/email-character-count/scripts/check_counts.py --json '{"Subject Line":"...","Preheader":"...","Body":"...","CTA":"..."}'```From the skill folder, use `python3 scripts/check_counts.py` instead.3. If the script cannot run, count manually with the same rules and the same output format.4. Report results. Do not rewrite copy unless the user asks.## OutputUse this table, then a one-line pass/fail summary:```markdown| Section | Count | Limit | Status ||---|---|---|---|| Subject Line | 38 | 40 | Pass || Preheader | 52 | 50 | Fail (2 over) |```Status values:- `Pass` — count is within the limit- `Fail (N over)` — count exceeds the limit- `Fail (missing)` — required section is empty- `Skipped` — optional section not providedOverall: **Pass** only if every required section passes and every provided optional section passes.## Input formatAccept labeled copy like this:```Subject Line: ...Preheader: ...H1: ...H2: ...H3: ...Body: ...CTA: ...Secondary CTA: ...```Optional headings may be omitted. Body may be multiple lines until the next section label.

Frequently asked questions