# The AI Agent Marketplace ROI Calculator

**Audience**: Engineering managers, VPs, CTOs

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## Why You Need This

The #1 blocker for marketplace adoption isn't technology. It's a VP asking "what's the ROI?" and getting a shrug. This guide gives you a concrete model to quantify the value.

## The ROI Model

### Inputs (fill in your numbers)

| Input | Description | Example Value |
| --- | --- | --- |
| `E` | Number of engineers in your org | 200 |
| `H` | Average hourly cost (salary + benefits + overhead) | $85/hr |
| `D` | Average days to onboard a new hire (productive coding) | 30 days |
| `P` | PRs reviewed per engineer per week | 5 |
| `I` | Incidents per month | 12 |
| `T_triage` | Average time to triage an incident (minutes) | 45 min |
| `T_review` | Average time for a thorough code review (minutes) | 30 min |
| `T_test` | Average time to write tests for a feature (hours) | 3 hrs |
| `D_dup` | Estimated % of AI agent work that's duplicated across teams | 30% |

### Cost of Doing Nothing (Annual)

| Cost Category | Formula | Example |
| --- | --- | --- |
| **Duplicated agent work** | `E * 2hrs/month * 12 * H * D_dup` | 200 \* 2 \* 12 \* $85 \* 0.3 = **$122,400** |
| **Inconsistent code quality** | `P * E * 5min/PR * 52weeks * H/60` | 5 \* 200 \* 5 \* 52 \* $1.42 = **$369,200** in review overhead |
| **Slow incident response** | `I * T_triage * 12 * H/60 * 3 engineers` | 12 \* 45 \* 12 \* $1.42 \* 3 = **$27,648** |
| **Extended onboarding** | `new_hires * 5days_saved * 8hrs * H` | 40 \* 5 \* 8 \* $85 = **$136,000** |
| **Knowledge loss** (attrition) | `departures * 40hrs_lost * H` | 30 \* 40 \* $85 = **$102,000** |
| **Total annual cost** |  | **~$757,000** |

### Cost of the Marketplace (Annual)

| Investment | Estimate |
| --- | --- |
| Initial setup (1 platform engineer, 2 weeks) | $6,800 |
| Seed 5 plugins (5 engineers, 1 day each) | $3,400 |
| Ongoing maintenance (0.25 FTE) | $44,200 |
| AI tool licenses (already paying for these) | $0 incremental |
| **Total annual cost** | **~$54,400** |

### ROI Calculation

```plaintext
Net Value    = Cost of Doing Nothing - Cost of Marketplace
             = $757,000 - $54,400
             = $702,600

ROI          = Net Value / Cost of Marketplace
             = $702,600 / $54,400
             = 12.9x return

Payback      = Cost of Marketplace / (Net Value / 12 months)
             = $54,400 / $58,550
             = < 1 month
```

> **Your mileage will vary.** These numbers are illustrative. The point is to give you a framework to plug in YOUR numbers and present to leadership.

## Beyond Dollars: Metrics That Matter

Financial ROI gets the initial "yes." These metrics sustain long-term support:

### Developer Experience Metrics

| Metric | How to Measure | Target |
| --- | --- | --- |
| **Time to first contribution** | Days from marketplace launch to first external plugin PR | < 30 days |
| **Plugin adoption rate** | % of repos with at least one marketplace plugin installed | \> 50% in 6 months |
| **Repeat usage** | % of installers who install a second plugin | \> 60% |
| **Developer NPS** | "Would you recommend the marketplace to a colleague?" (0-10) | \> 40 |

### Quality Metrics

| Metric | How to Measure | Target |
| --- | --- | --- |
| **Security findings per PR** | Automated catches from marketplace security rules | Track trend (should increase then plateau) |
| **Incident MTTR** | Mean time to resolve with vs. without marketplace plugins | 20% reduction |
| **Test coverage delta** | Coverage change in repos after test-writer adoption | +10% average |
| **Onboarding time** | Days to first meaningful PR for new hires | 30% reduction |

### Ecosystem Health Metrics

| Metric | How to Measure | Target |
| --- | --- | --- |
| **Total plugins** | Count in marketplace | 10+ in 6 months |
| **Active contributors** | Unique authors of merged plugin PRs per quarter | 5% of engineering org |
| **Plugin freshness** | % of plugins updated in last 90 days | \> 70% |
| **Cross-team reuse** | Plugins used by 3+ teams | \> 50% of plugins |

## How to Present This to Leadership

### The One-Slide Pitch

```plaintext
PROBLEM:  200 engineers using AI tools independently = chaos
          30% duplicated work, zero governance, knowledge silos

SOLUTION: Internal AI Agent Marketplace
          Shared plugins, org-wide rules, built-in compliance

COST:     ~$54K/year (0.25 FTE + 2-week setup)

VALUE:    ~$700K/year in recovered productivity
          + Consistent code quality across all teams
          + Compliance by default (not by audit)
          + Institutional AI knowledge that survives attrition

ASK:      1 platform engineer for 2 weeks
          Then 25% of their time ongoing

ROI:      12.9x return, payback in < 1 month
```

### The Three Questions You'll Get

**"Can't we just write a wiki page with prompts?"** A wiki is where prompts go to die. Nobody discovers them, nobody updates them, and there's no governance. The marketplace has a CLI (`marketplace browse`), version control, automated testing, and telemetry. It's the difference between a Google Doc of recipes and a restaurant kitchen.

**"We already have GitHub Copilot / Claude / Cursor licenses. Isn't that enough?"** Those tools are the engines. The marketplace is the fuel. Without shared rules and skills, each engineer drives in a different direction. The marketplace aligns them without taking away their choice of vehicle.

**"What if engineers don't contribute?"** They will, if consuming is easy. The contribution flywheel starts with consumption: install a plugin, find it useful, notice a gap, submit a PR. Your first 5 plugins come from the platform team. The next 50 come from the engineers who used those 5.

## Template: Quarterly Business Review

Use this template to report marketplace impact quarterly:

```markdown
## AI Agent Marketplace: Q[X] Review

### Adoption
- Plugins available: [N] (up from [N-1])
- Repos with marketplace installed: [N] / [Total] ([%])
- Monthly active plugin installs: [N]
- Unique contributors this quarter: [N]

### Impact
- Estimated engineering hours saved: [N] hrs
- Security findings caught by marketplace rules: [N]
- Average incident MTTR with marketplace: [N] min (down from [N] min)
- New hire onboarding time: [N] days (down from [N] days)

### Top Plugins by Usage
1. [plugin-name]: [N] installs, [N] active repos
2. [plugin-name]: [N] installs, [N] active repos
3. [plugin-name]: [N] installs, [N] active repos

### What's Next
- [Planned plugin or initiative]
- [Planned plugin or initiative]
```

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*This is a bonus post in the AI Agent Marketplace series.*