# Market data

URL: /systems/marketing/market-data · Id: `capability:market-data`

> Market data measures the outside market: search demand, rankings, links, answer citations, running ads and social reach, each with provenance.

Market data measures the outside market: search demand, rankings, links, answer citations, running ads and social reach. Every reading carries its provenance.

## Contract
A reading is a record in the [Startup](/business/nouns/startup)'s namespace, never a screenshot or a number in a chat. It names what was measured, when, by which method and over what sample. A reading older than its [Setting](/business/nouns/setting)'s maximum age is measured again before anyone acts on it.

| Measure | Reading | Read by |
| --- | --- | --- |
| Search demand | Monthly volume, difficulty and trend per [Keyword](/business/nouns/keyword) | The [SEO](/systems/seo) [System](/business/nouns/system) and the opportunity map |
| Rankings | Rank of each [Page](/business/nouns/page) per Keyword, tracked daily | SEO and demand [Plays](/business/nouns/play) |
| Links | Referring domains and their authority, per Page | SEO, outreach |
| Answer citations | Which answers on ChatGPT, Perplexity, Gemini, Claude and Google AI Overviews cite a Page | Answer-engine Plays |
| Running ads | The [Ads](/business/nouns/ad) a competitor runs on each ad venue, with first and last seen | The [Ads](/systems/ads) System |
| Social reach | Followers and engagement per account, and an [Audience](/business/nouns/audience)'s size | The [Social](/systems/social) System |

Every lookup is metered and checked against the Startup's [Limits](/business/nouns/limit). A reading that names a person passes [Suppression](/business/nouns/suppression) first. Readings feed [Evidence](/business/nouns/evidence) for a [Hypothesis](/business/nouns/hypothesis) about demand, never a [Metric](/business/nouns/metric) about the Startup's own [Customers](/business/nouns/customer).

## Verbs
| Verb | Object | Event |
| --- | --- | --- |
| [Keyword.get](/business/nouns/keyword/get) | [Keyword](/business/nouns/keyword) | None. |
| [Keyword.list](/business/nouns/keyword/list) | [Keyword](/business/nouns/keyword) | None. |
| [Keyword.measure](/business/nouns/keyword/measure) | [Keyword](/business/nouns/keyword) | [`Keyword.measured`](/business/events/Keyword.measured) |
| [Domain.benchmark](/business/nouns/domain/benchmark) | [Domain](/business/nouns/domain) | [`Domain.benchmarked`](/business/events/Domain.benchmarked) |

## Interfaces
- [API](/code/api/reference)
- [SDK](/code/sdk/reference)
- [CLI](/code/cli/reference)
- [MCP](/code/mcp/reference)

## Example
`taxcalc.tools` targets "freelance tax calculator", which draws 12,000 searches a month. Its calculator Page ranks 14th. After a rewrite, the Page ranks 6th, and Perplexity starts citing it within three weeks.