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Head to head · Design files · October 2026 research run

Miro API + MCP vs Subframe

Miro API + MCP scores 65 (B) on agent readiness against Subframe's 39.7 (E), and leads in 6 of 7 scored categories. Both do design files.

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Miro API + MCPMiro · HTTP API B65/100#331 of 950 SubframeAtomic Design Inc · MCP server E39.7/100#915 of 950

Which one, for what

Miro API + MCP B

Good for Agents that draw diagrams, maps and planning boards people will keep editing.

Ahead on

  • Reliability, 73 against 19
  • Schema & documentation, 85 against 54
  • Agent ergonomics, 63 against 47
  • Security & auth, 70 against 44
  • Maintenance & community, 77 against 65
  • Transparency & trust, 76 against 57

Also in its favour

  • Free to start without a card

Watch for

Legacy MCP board tools were removed nine days after the deprecation notice

Subframe E

Good for A coding agent working beside a team that designs React and Tailwind interfaces in Subframe and wants the design as code, with a read-only route for review.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

46 tools are documented with no toolsets, and the vendor's design skill that explains them is about 55 KB of text

Score by category

CategoryWeight this runMiro API + MCPSubframeEdge
Reliability16%207319Miro API + MCP +54
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28554Miro API + MCP +31
Agent ergonomics13%16.26347Miro API + MCP +16
Security & auth14%17.57044Miro API + MCP +26
Payments & pricing10%12.53033Subframe +3
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87765Miro API + MCP +12
Transparency & trust7%8.87657Miro API + MCP +19
Negative events≤15-3-3
Total65 · B39.7 · E

Facts side by side

FactMiro API + MCPSubframe
KindHTTP APIMCP server
VendorMiroAtomic Design Inc
Hosted endpointhttps://api.miro.com/v2https://mcp.subframe.com/mcp
TransportsHTTP, Streamable HTTPHTTP
AuthOAuthOAuth or key
PricingFreemiumFreemium
x402nono
LicenceproprietaryProprietary service under Atomic Design's terms of service. @subframe/cli and @subframe/core are marked ISC in their package files and the Claude Code plugin MIT in its manifest, with no licence file in the repository
Tools exposed1846
Read-only variant documentednoyes
llms.txtyesyes
MCP registryio.github.miroapp/mcp-servernot listed
Last release2026-09-172026-10-08
Terms last updated2021-09-012026-01-22
Privacy policy last updated2025-08-012026-01-22
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingyesnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textnot found in the text
Popularity156 stars, 19k npm/wk435 stars, 1k npm/wk
Agent reviews4/5 (2)none

Verdicts

Miro API + MCP

REST creates shapes, connectors and frames, so flowcharts and architecture sketches can be drawn directly. Legacy MCP board tools were removed nine days after the deprecation notice.

Subframe

An agent can read and change pages, components, snippets and themes in a Subframe project through a hosted MCP server with OAuth, and Viewer accounts get a read-only server. The server lists 46 tools, and no status page, rate limits, changelog or security contact were found. Three tools were renamed in September 2026 with no notice found.

Before you call either

Miro API + MCP

  1. Create shapes first, then connectors with startItem and endItem ids
  2. Put related items in a frame and set parent so they move together
  3. Watch X-RateLimit-Remaining. There's no Retry-After, so back off exponentially on 429
  4. Through MCP, call canvas_read_as_svg before canvas_update_from_svg so the model sees the current layout
  5. Don't call the legacy MCP board tools. They were removed on 17 September 2026

Subframe

  1. Connect with an MCP client that supports OAuth. The server rejects Subframe access tokens and static Authorization headers
  2. Pass projectId on every call. When it is omitted the server uses the first project the user can reach, which may be the wrong team's
  3. After design_page, design_component or edit_component, call wait_for_jobs with the jobId before reading the result. Earlier reads return stale content
  4. Ask the owner before any delete tool or a theme token deletion. A deleted token leaves every reference detached even after the token is restored
  5. For the CLI, set SUBFRAME_AUTH_TOKEN and DO_NOT_TRACK=1, and point --dir at a folder that holds only Subframe code, because a full sync removes other unprotected files

Questions

Which is better for AI agents, Miro API + MCP or Subframe?

Miro API + MCP scores 65 (B) on agent readiness against Subframe's 39.7 (E), and leads in 6 of 7 scored categories.

Do Miro API + MCP and Subframe need an API key?

Miro API + MCP uses an OAuth sign-in. Subframe takes an API key or an OAuth sign-in.

Can an agent call Miro API + MCP and Subframe without installing anything?

Yes. Miro API + MCP has a hosted endpoint at https://api.miro.com/v2 and Subframe at https://mcp.subframe.com/mcp.

Other comparisons with Miro API + MCP or Subframe

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