Methodology

Evidence first. Boundaries visible.

The Atlas separates first-party facts, source inventory, editorial assessment, proposed designs, and unresolved implementation questions.

Inclusion

A platform belongs when it owns consequential customer, campaign, content, identity, revenue, workflow, media, or operational state; exposes meaningful access; anchors a significant category; or demonstrates a distinct interface-separation pattern.

“Best in class” here means architecturally instructive and strategically relevant—not highest market share or an endorsement.

Research layers

  1. Representative platform source: a first-party page used to summarize the platform’s accessible core.
  2. Targeted agent-role review: first-party evidence used to distinguish providers, hosts, bridges, infrastructure, and developer-context servers.
  3. Supporting source inventory: official links retained for implementation research but not necessarily reopened endpoint by endpoint.

SQL, structured-query, and Reverse ETL evidence

These capabilities use explicit, per-profile evidence records rather than connector-name inference. SQL can mean a native SQL editor, warehouse-mediated SQL, or a vendor query surface; GraphQL, DAX, GROQ, HogQL, SOQL, and similar languages are labeled as structured query rather than silently described as database SQL.

Reverse ETL is classified separately from MCP. A platform can support warehouse activation or writeback without exposing that action through its MCP server, and a database connector alone does not establish SQL access to the platform.

Current targeted access audit: 49 reviewed records across 40 profiles. Each record includes a first-party source, scope note, review date, and a boundary describing where the query or activation actually executes.

Tool and connector catalogs

Registries and directories are discovery aids, not proof that a server is first-party or that a listed capability is currently available. A name enters a public profile only after it is checked against first-party documentation, a first-party source repository, a first-party machine-readable catalog, or a directly observed tools/list response.

  • MCP tools stay separate from connectors. A tool is an operation exposed by a particular MCP server; a connector links a product to another system or data source.
  • Scope is explicit. Each catalog states the server variant or product surface, evidence basis, completeness, source, and review or observation date.
  • Partial lists stay partial. Capability families are not expanded into invented tool names, and marketplace apps are not relabeled as native connectors.
  • Discovery data stays private. Unreviewed registry matches and machine-extracted candidates are not copied into the public site data directory.
Current reviewed catalog coverage: 25 catalogs with 585 named items across 17 profiles. Profiles without a reviewed exact catalog keep their broader capability evidence without implying an exhaustive list.

Evidence labels

Verified fact

Tied to a reviewed first-party source for the dated snapshot.

Source inventory

An official link recorded for deeper research; reachability and current scope should be rechecked.

Editorial assessment

System role, maturity, inclusion rationale, or architectural interpretation.

Proposed design

An interface or composition idea—not a claim that the vendor ships it.

Access-maturity model

  1. Application-bound: the native interface remains the primary practical surface.
  2. Extensible SaaS: APIs, events, SDKs, or extensions support meaningful external applications.
  3. Agent-accessible SaaS: governed capabilities are available through MCP or an equivalent agent surface.
  4. BYO-UI-ready platform: multiple access modes, identity, action controls, governance, and externally built experiences form a credible platform architecture.

The level is not a quality grade. A focused Level 2 API may be a better fit for a particular job than a broad but immature agent surface.

What still requires implementation validation

  • Exact endpoints, tools, and event payloads
  • OAuth registration, scopes, service accounts, and delegated identity
  • Plan, region, beta, preview, partner, and administrative requirements
  • Rate limits, quotas, data freshness, retention, and asynchronous behavior
  • Terms, automated-publishing restrictions, AI-processing terms, and application review
  • Idempotency, rollback, audit, observability, prompt-injection defenses, and security testing
Known boundary: 539 supporting inventory records were structurally normalized but not individually reopened in the final validation pass. The site does not claim permanent URL reachability or exhaustive endpoint coverage.

Coverage

158 profiles across 15 categories

23

Marketing automation, lifecycle & CDP

22

Analytics, SEO & experimentation

18

Content, CMS, creative & DAM

17

CRM, revenue & customer

11

Advertising & media buying

11

Media generation, video & localization

9

Automation, data & MCP bridges

8

Social, PR & community

7

Work & collaboration

7

Publishing, newsletters & creator platforms

7

Interface hosts, builders & integration infrastructure

6

Events & live engagement

5

Commerce & payments

5

Research, forms & feedback

2

Partnerships & ecosystem