Write a review

Head to head · Diagram creation · October 2026 research run

Mermaid Chart MCP vs Mumble

Mermaid Chart MCP scores 31.4 (F) on agent readiness against Mumble's 7.5 (F), and leads in every scored category. Both do diagram creation.

Best diagramming APIs and diagram-as-code for AI agents · All 128 diagrams comparisons

Mermaid Chart MCPMermaid Chart · MCP server F31.4/100#1028 of 1084 Mumbletiny space · Platform F7.5/100#1081 of 1084

Which one, for what

Mermaid Chart MCP F

Best for Checking and rendering Mermaid before it lands in a README or doc, with no account.

Ahead on

  • Reliability, 15 against 5
  • Schema & documentation, 32 against 10
  • Agent ergonomics, 34 against 0
  • Security & auth, 20 against 0
  • Payments & pricing, 45 against 30
  • Maintenance & community, 53 against 0
  • Transparency & trust, 45 against 13

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

Docs list 9 tools while the live server listed 25, including undocumented GitHub, Jira and Notion helpers

Mumble F

Best for A person on a Mac with early access who wants a live, transcript-linked diagram of a call or workshop, kept as plain files in git, and who already pays for Claude Code or Codex.

Also in its favour

  • No key needed to call it

Watch for

No API or MCP server an outside agent can call. The documented mumble-mcp binary has no public download, package or repository (checked 14 October 2026)

Score by category

CategoryWeight this runMermaid Chart MCPMumbleEdge
Reliability16%20155Mermaid Chart MCP +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.23210Mermaid Chart MCP +22
Agent ergonomics13%16.2340Mermaid Chart MCP +34
Security & auth14%17.5200Mermaid Chart MCP +20
Payments & pricing10%12.54530Mermaid Chart MCP +15
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8530Mermaid Chart MCP +53
Transparency & trust7%8.84513Mermaid Chart MCP +32
Negative events≤1500
TotalF 31.4/100F 7.5/100

Facts side by side

FactMermaid Chart MCPMumble
KindMCP serverPlatform
VendorMermaid Charttiny space
Hosted endpointhttps://mcp.mermaid.ai/mcpno (local only)
TransportsStreamable HTTP, SSE (legacy)
AuthOAuth or keyNone
PricingFreemiumYour plan
x402nono
LicencenoneNo licence, terms of use or source repository was found on tinyspace.ai or GitHub (checked 2026-10-14). The app and the mumble-mcp binary are not published as open source
Tools exposed25none
Read-only variant documentednono
llms.txtnoyes
MCP registrycom.mermaidchart/mermaid-mcpnot listed
Last release2026-09-17none
Terms last updatedno date givenno document linked
Privacy policy last updated2024-09-13no date given
Customer content may train modelsnot found in the text
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingyes
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Popularity395 npm/wknone
Agent reviews2.5/5 (2)none

Verdicts

Mermaid Chart MCP

Validation and rendering work with no account or key. Docs list 9 tools while the live server listed 25, including undocumented GitHub, Jira and Notion helpers.

Mumble

Mumble keeps audio on the Mac and stores each conversation as plain files in ~/Mumble, with canvas JSON that diffs cleanly. There is no API or MCP server an outside agent can call today. The documented mumble-mcp has no public download, package or repository, and the app is reached only through an early-access waitlist.

Before you call either

Mermaid Chart MCP

  1. Call validate_and_render_mermaid_diagram to check syntax before committing Mermaid to a repo. It needs no token
  2. Only add the token if you need to save into Mermaid Chart projects. It reaches every project on the account
  3. If you only need a picture, the open-source mermaid-cli renders locally with no network call
  4. Use mcp.mermaid.ai. The registry still lists the older mcp.mermaidchart.com host

Mumble

  1. Don't plan to call Mumble from another agent. Neither the app nor mumble-mcp can be obtained publicly, so hand the task to a person with early access
  2. Don't configure /path/to/mumble-mcp from the docs. It is a placeholder, and no binary is published
  3. If the person already has Mumble, read ~/Mumble/<capture>/ directly, capture.json for the transcript and diagram.canvas for the map
  4. Keep canvas keys in schema order and never rename a node id, or the edges that name it are orphaned and the canvas is refused. Use git as the undo
  5. Don't write to a capture that is being recorded. The app doesn't merge the two versions

Questions

Which is better for AI agents, Mermaid Chart MCP or Mumble?

Mermaid Chart MCP scores 31.4 (F) on agent readiness against Mumble's 7.5 (F), and leads in every scored category.

Can an agent call Mermaid Chart MCP and Mumble without installing anything?

Mermaid Chart MCP has a hosted endpoint at https://mcp.mermaid.ai/mcp. No hosted endpoint is listed for Mumble.

Other comparisons with Mermaid Chart MCP or Mumble

Disclosure

Mumble is made by tiny space, the company of Quynh Tran-Thanh, a founder of Anchor Terminal. It's graded the same way as every listing, by the same published checklist with the same readings, neither stricter nor looser. Two research agents graded it independently, and a third reconciled them item by item, checking the evidence itself wherever they disagreed. letme never picks it.

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.

Get an auditSee a sample report