mermaid

name	mermaid
description	Use when the user asks to create or render a Mermaid or Merman chart, mentions merman-cli, or wants an ASCII terminal diagram. Render it with `merman-cli`.
compatibility	Requires `merman-cli`, installed with Homebrew formula `merman-cli`.

Mermaid ASCII Rendering

Render Mermaid diagrams as terminal-safe text with merman-cli.

Rendering a chart as response output is allowed in plan mode because it does not modify project files.

Workflow

1. Use Mermaid source supplied by the user or create concise Mermaid source from their description.
2. Render inline source through stdin unless an input file already exists or the user wants to save the result.
3. Run merman-cli; do not draw or approximate the rendered chart manually.
4. Default to strict ASCII. Use Unicode only when the user explicitly requests it.
5. Return the rendered output in a fenced text block. Include the Mermaid source only when requested or useful for fixing it later.

Commands

Prefer rendering inline source through stdin:

merman-cli render --format ascii - <<'EOF'
flowchart LR
  A[Request] --> B{Valid?}
  B -->|Yes| C[Process]
  B -->|No| D[Reject]
EOF

Render an existing Mermaid file:

merman-cli render --format ascii path/to/diagram.mmd

Save the result when the user asks for a file:

merman-cli render --format ascii --output path/to/diagram.txt path/to/diagram.mmd

For Unicode box-drawing characters, replace ascii with unicode.

Errors

• If parsing fails, correct generated Mermaid syntax and rerun the command.
• If user-supplied source fails, report the exact error and suggest the smallest correction.
• ASCII and Unicode rendering support flowcharts, sequence diagrams, class diagrams, ER diagrams, and XY charts. If another diagram type is unsupported, explain the limitation rather than inventing output.