Crate duckduckgo_search_cli 

duckduckgo-search-cli

Rust CLI for searching DuckDuckGo via pure HTTP, with structured JSON output for LLM consumption. No paid API. No Chrome (during the search phase). No cache. Universal cross-platform (Linux including Alpine/NixOS/Flatpak/Snap, macOS including Apple Silicon, Windows including cmd.exe and PowerShell).

Module Structure

Module	Responsibility
cli	Clap structs (command-line argument parsing).
http	reqwest::Client construction and User-Agent selection.
search	URL building and HTTP request to the DuckDuckGo endpoint.
extraction	HTML parsing with scraper and ad filtering.
pipeline	Single/multi orchestration, deduplication and source reading.
parallel	Multi-query fan-out with JoinSet, Semaphore, CancellationToken.
output	JSON serialization and stdout writing (ONLY module with println!).
platform	Cross-platform initialization (UTF-8 on Windows, TTY detect).
types	Shared structs and enums.
error	Error codes and exit codes.
content	HTTP + readability extraction for --fetch-content (iter. 5).
content_fetch	Parallel fan-out + per-host rate-limit (iter. 5 / 6).
selectors	Loading of external SelectorConfig (iter. 6).
signals	Cross-platform signal handlers (SIGPIPE, Ctrl+C).
config_init	init-config subcommand (iter. 6).
paths	Path validation and sanitization for I/O.
browser	Headless Chrome cross-platform under feature chrome (iter.7).

Entry Point

The public function run is called by main.rs and returns an exit code as specified in section 17.7 of the specification.

Modules

aggregation

Result aggregation across sub-queries for the deep-research pipeline.

browser

Cross-platform detection and launch of headless Chrome via chromiumoxide.

cli

CLI argument definitions via clap derive.

config_init

Implements the init-config subcommand — copies TOMLs embedded in the binary to the user’s configuration directory, allowing local editing without recompiling.

content

Full text content extraction from URLs (flag --fetch-content).

content_fetch

Parallel fan-out for content extraction (flag --fetch-content).

decomposition

Query decomposition for deep-research fan-out.

deep_research

Deep research subcommand — query fan-out, aggregation, and synthesis.

error

Structured error codes as defined in specification section 14.3.

extraction

Extraction of search results from DuckDuckGo HTML.

http

reqwest::Client construction and User-Agent selection.

identity

Browser identity pool for adaptive anti-bot rotation (WS-26).

output

Formatting and emission of the final result to stdout or a file.

parallel

Multi-query parallelism with JoinSet, Semaphore, staggered launch and CancellationToken.

paths

Path validation and sanitization for I/O operations.

pipeline

Orchestration of the CLI execution flow.

platform

Platform detection and cross-platform initialization.

search

URL construction and search request execution for DuckDuckGo.

selectors

Lazy loading of SelectorConfig with precedence:

signals

Cross-platform signal handlers for the CLI binary.

synthesis

Heuristic synthesis of an aggregated result list into a single report.

types

Shared data types used across the application.

Functions

run

Library entry point. Called by main.rs.