Chapter 8: Interactive Demo and Reporting

Chapter Status: ⚠️ The command exists but cannot run in a cargo install pmat build

Last updated: 2026-08-25 PMAT version: pmat 3.32.0

⚠️ Historical, as of pmat 3.32.0 (2026-08-25). pmat demo does not run in the build you get from cargo install pmat.

This chapter described pmat 2.213.1 and presented 55 working examples. All 55 fail against 3.32.0, for two independent reasons:

• pmat demo takes no positional path. Forty of the examples were written as pmat demo .; clap rejects that with “unexpected argument found” and exits 2. The path goes in -p / --path.
• The demo is behind a non-default Cargo feature. Even with the path corrected, every invocation — --cli, --protocol mcp, the web server, all of them — exits 1 with Error: Demo feature not enabled. Build with --features demo. pmat demo --help still prints, which is why this chapter passes the book’s command-existence gate while none of it works.

The dashboards, JSON payloads and tables the old chapter pasted cannot be reproduced from an installed pmat. They have been removed rather than reprinted as if verified. What remains is the invocation form, the real error, and where to go instead.

For code analysis with output you can actually get today, read Chapter 5 (pmat analyze) and Chapter 9 (pmat report).

What pmat demo Was For

pmat demo bundles pmat’s analyses into a presentation: a CLI summary, an interactive web dashboard, or a scripted walk through the MCP tool surface. It exists to show what pmat can do without asking the viewer to learn the subcommands first.

It is a demonstration harness, not an analysis command. Nothing it reports is unavailable from pmat analyze and pmat report, which is why shipping it behind a feature flag costs installed users nothing but this chapter.

Verified: What Happens When You Run It

pmat demo -p . --cli

Error: Demo feature not enabled. Build with --features demo

Exit code 1. The same for every mode:

pmat demo -p . --cli -f json
pmat demo --repo gh:owner/repository
pmat demo --url https://github.com/owner/repository.git

Error: Demo feature not enabled. Build with --features demo

The help text is candid about it — pmat demo --help opens with:

cargo install pmat produces a build in which every demo mode (including --cli) exits 1 with “Demo feature not enabled”, so all the flags below are inert.

Enabling It

The demo feature does exist in the published crate. cargo add --dry-run pmat --features demo resolves cleanly against pmat 3.32.0 (76 activated features rather than the default 69), so this is the supported route:

cargo install pmat --features demo

That build has not been exercised for this chapter, and no output from it is reproduced here. If you build it and the behaviour differs from the flag reference below, the flag reference is what --help printed, not what the demo did.

Flag Reference

These are the flags pmat demo --help lists in 3.32.0. They all parse; none of them does anything in the default build. The path is -p, never positional.

Correct invocation forms, for when you have a build that supports them:

pmat demo -p . --cli
pmat demo -p . --cli -f json
pmat demo -p . --port 3000 --no-browser
pmat demo -p . --protocol mcp --show-api
pmat demo -p . --cli --target-nodes 20 --centrality-threshold 0.2
pmat demo --repo gh:rust-lang/rustlings --cli

Each of these exits 1 in the default build. They are printed as forms, not as worked examples.

What to Use Instead

Everything the demo displayed has a first-class command that works in the build you already have:

pmat serve is a real, compiled-in HTTP server, but it serves the MCP tool surface, not a dashboard. It is not a drop-in replacement for the demo’s web UI; there is no HTML dashboard in the default build.

Summary

pmat demo is a feature-gated presentation tool. In cargo install pmat it resolves, prints help, and refuses to run.

Key takeaways:

• -p, not a positional path. That alone broke 40 of this chapter’s 55 examples even before the feature gate.
• Every mode exits 1 with Demo feature not enabled in the default build.
• cargo install pmat --features demo is the documented route; the demo feature is real in the published 3.32.0 crate.
• No demo output is reproduced in this chapter, because none of it can be produced from an installed pmat.