# Napkin Math

**Canonical:** https://apis.io/providers/napkin-math/  
**Website:** https://napkinmath.club  
**APIs profiled:** 0

Napkin Math is a personalized AI food journal from Paper Star (a Y Combinator company, founded 2026 in San Francisco by Manuel Castro, Claire Nord, and Jynnie Tang). Marketed as "an AI nutrition coach in your pocket," it is a simple, beautiful food diary that helps people log meals and understand their eating habits over time. The product is a consumer mobile application rather than a developer platform: as of this profile Napkin Math publishes no public API, developer documentation, SDKs, OpenAPI, MCP server, or /.well-known discovery surface. This entry is maintained in the API Evangelist network as a company profile and enrichment lead; it will be upgraded to carry API artifacts if and when Napkin Math or Paper Star exposes a public API surface.

## Kin Score — 9.0 / 100 (minimal)

Scored 2026-08-19 under rubric 0.12.0. Trend: flat (-1.5 from 10.5).

| Facet | Score |
|---|---|
| Discoverability | 50.0 |
| Contract Quality | 0.0 |
| Governance | 0.0 |
| Contract Governance | 0.0 |
| Operational Transparency | 0.0 |
| Developer Ergonomics | 0.0 |
| Commercial Clarity | 21.1 |
| Access Clarity | 21.1 |

Regulatory layer — **Health**: 17.5 (matched via tags).

## Agent readiness — 0.0 (human-only)

| Dimension | Value |
|---|---|
| Spec Presence | no |
| Agentic Access | no |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | no |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | no |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## Access

Unknown — onboarding: unknown, pricing: unknown, trial: no (confidence: low).

## Security (1)

- **Napkin Math Domain Security** — TLSv1.3 · HSTS · DMARC

## Tags

Company, Nutrition, Food Journal, Health, Diet, Artificial Intelligence, Consumer Application, Mobile Application, iOS

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/napkin-math/). Scores are computed from the provider's own public artifacts under a published rubric.