Black SparrowBlack Sparrow

CLI Reference

Command: sparrow inspect

Instant single-page developer X-ray for inspecting HTTP status, DOM metadata, and schemas.

The inspect command provides an instant, developer-focused X-ray of any single webpage without crawling the entire website.

Terminal
Terminal
sparrow inspect <URL> [OPTIONS]

It is ideal for testing blog posts, landing pages, or pricing tables locally while developing.

What inspect Checks

When you inspect a URL, Black Sparrow evaluates:

  • ⏱️ Network & Performance: HTTP status (200, 301, 404), Time To First Byte (TTFB), total fetch duration, and compressed content size.
  • 🏷️ Essential Metadata: Page <title> length and pixel width, <meta name="description">, and robots directives (noindex, nofollow).
  • 🔗 Canonicalization: Canonical tag target, self-referencing check, and HTTP Link headers.
  • 📑 Heading Structure: Full H1 through H6 hierarchy, checking for missing H1s, multiple H1s, or skipped heading levels.
  • 🖼️ Image Health: Images missing descriptive alt text and images missing explicit width and height attributes (which cause Cumulative Layout Shift).
  • 📱 Social Sharing Cards: OpenGraph (og:title, og:image, og:type) and Twitter Card tags.
  • 🧩 Structured Data: Detection and syntax validation of JSON-LD schemas (e.g. Article, Product, Organization, FAQPage).

Options & Flags

OptionDefaultDescription
<URL>RequiredWebpage URL to inspect.
-f, --format <FORMAT>"terminal"Output format: terminal (ANSI color) or json.
-u, --user-agent <STR>"BlackSparrow/1.0"Custom HTTP User-Agent.
--render-jsfalseRenders client-side JavaScript via Headless Chrome before inspection.

Example Usage

Instant Terminal Inspection

Terminal
Terminal
sparrow inspect https://example.com/blog/rust-concurrency

Sample output:

================================================================================
                         PAGE INSPECTION X-RAY
================================================================================
URL              : https://example.com/blog/rust-concurrency
Status Code      : 200 OK (TTFB: 48ms, Content: 24.8 KB)
 
METADATA:
  Title          : Rust Concurrency in Practice - High Performance Systems (56 chars)
  Description    : Learn how to leverage Tokio green tasks and channels. (61 chars)
  Canonical      : https://example.com/blog/rust-concurrency [Matches URL]
  Robots         : INDEX, FOLLOW
 
HEADINGS HIERARCHY:
  H1 (1)         : Rust Concurrency in Practice
  H2 (4)         : 1. Green Tasks | 2. Channels | 3. AIMD Control | 4. Benchmarks
  H3 (6)         : Sub-sections verified cleanly
 
STRUCTURED DATA (JSON-LD):
  Found          : BlogPosting, BreadcrumbList
  Status         : Valid schema.org syntax
 
FINDINGS (1 Warning):
  [WARNING]      : IMG-002: 2 images are missing explicit width/height attributes

JSON Output for Scripts and Git Hooks

Export the raw inspection data as JSON to integrate with pre-commit hooks or automated linters:

Terminal
Terminal
sparrow inspect http://localhost:3000/about -f json > inspect_result.json