name: flowchart description: Choose a flowchart when the user needs a readable decision or process path with a clear start, sequence, branch, merge, or end.

Flowchart

What and why

A flowchart is a control-flow story: work moves from an entry point through actions and decisions to one or more outcomes. Choose it for procedures, troubleshooting, algorithms, approvals, and “what happens next?” explanations. It is not a good fit for rich business semantics, timed interactions between participants, or a large dependency network.

Model it

State the scope and one reader question in the title.
Identify start/end outcomes before filling in steps.
Use verb-first action labels and phrase decisions as questions with labeled exits.
Make the normal path visually dominant; keep exception paths explicit.
Merge paths when they become equivalent, and avoid crossing connectors.

Use conventional symbols where the audience expects them: process, decision, terminator, input/output, and connector. ISO 5807 remains the relevant flowchart reference; use its notation when interchange or formal review matters. See flowchart conventions.

Story and styling

The useful story is “how a case gets from here to there.” Keep one direction, consistent spacing, and short labels. Reserve color for semantic emphasis such as risk, exception, or ownership; provide shape or text cues too. Put explanatory detail in notes or adjacent prose rather than turning every node into a paragraph.

Renderer routing

Prefer mermaid for quick Markdown-friendly flowcharts, graphviz when automatic graph layout matters, plantuml for a source-controlled formal diagram, or d2 for a polished architecture/process sketch. blockdiag is suitable for simple block-oriented paths. Preserve an explicitly requested renderer and adapt the model to its syntax.

Review

Is there one clearly stated scope and outcome question?
Can every decision exit be followed and understood?
Are loops, retries, and failure outcomes visible?
Does the layout have a reading direction and minimal line crossings?
Are symbols, labels, contrast, and text alternatives usable in the target output?

Limits and opportunities

The renderers above do not provide a guaranteed ISO 5807 interchange validator. If strict symbol conformance or machine validation becomes a product requirement, add a flowchart semantic linter or an ISO-profile integration.