Unit Economics

What it does

When your agent uses it

• Tasks that involve Financial modeling

Example prompts

• “unit economics”
• “LTV/CAC”
• “contribution margin”
• “/unit-economics”

Workflow steps

4 steps, taken from the first numbered list in SKILL.md.

1. 1Retention Pattern Over Time: Identify stabilization point
2. 2Cross-Cohort Comparison: Are newer cohorts improving?
3. 3NDR/NRR Decomposition: Track expansion vs. contraction vs. churn separately
4. 4LTV Convergence Estimation: Estimate actual LTV from cohort data

What it can do on your machine

Read from SKILL.md and the folder at commit 8e8d35c. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are markdown).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Unit Economics loads about 1.2k tokens when it runs. Until then it costs about 108 tokens; SKILL.md has 332 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~108

When it runs · the whole SKILL.md, loaded when a task matches

~1.2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from revfactory/harness-100 at commit 8e8d35c, republished under its Apache-2.0 licence (© revfactory). 332 words, ~1,220 tokens.

name

unit-economics

description

A specialized skill providing a Unit Economics analysis framework. Used by the revenue-modeler agent when designing revenue models and calculating LTV, CAC, and contribution margin. Automatically applied in contexts such as 'unit economics', 'LTV/CAC', 'contribution margin', 'cohort analysis', 'payback period'. However, direct CRM data extraction and real-time customer analytics are outside the scope of this skill.

LTV = ARPA x Gross Margin / Monthly Churn Rate

LTV = Sum(t=1→inf) [ARPA_t x GM x Retention_t / (1+d)^t]

ARPA_t = Average revenue per account at month t (reflecting expansion/contraction)
GM = Gross Margin
Retention_t = Retention rate at month t
d = Monthly discount rate

CAC = (Marketing Cost + Sales Cost) / New Customers

Blended CAC = Total S&M / Total New Customers
Paid CAC = Paid Channel Cost / Paid Channel New Customers
Organic CAC = Overhead Allocation / Organic New Customers

CAC Payback (months) = CAC / (ARPA x Gross Margin)

LTV/CAC = LTV / CAC

Revenue 100%
  (-) Variable Costs (COGS, shipping, transaction fees)
  = Contribution Margin 1 (CM1) — Per-transaction profitability
  (-) Variable Marketing (performance marketing)
  = Contribution Margin 2 (CM2) — Profitability including marketing efficiency
  (-) Fixed Cost Allocation (labor, infrastructure, other)
  = Contribution Margin 3 (CM3) — Business unit profitability

| Sign-up Month | M0 | M1 | M2 | M3 | M6 | M12 |
|--------------|-----|-----|-----|-----|-----|------|
| 2024-01 | 100% | 85% | 78% | 73% | 62% | 48% |
| 2024-04 | 100% | 88% | 82% | 77% | 68% | - |
| 2024-07 | 100% | 90% | 85% | 80% | - | - |

Revenue = Target Market Size (SAM)
        x Reachable Ratio
        x Conversion Rate
        x Average Order Value
        x Repeat Purchase Frequency

© revfactory, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in en/53-financial-modeler/.claude/skills/unit-economics of revfactory/harness-100.

Open the folder on GitHubat commit 8e8d35c