pi-wierd-web

Web tools for the pi coding agent:

• web_search — Anthropic-powered server-side search with citations.
• web_fetch — headless-Chrome fetch + trafilatura extraction, with optional sub-agent distillation. Ported from pi-web-fetch (hooks/extension system intentionally omitted).

Tools

web_search

A one-shot POST /v1/messages call backed by Anthropic's server-side web_search_20250305 tool. Returns a synthesized answer + citations + raw source list. Never touches the agent's main turn stream.

Parameters:

• query (required) — the search query
• max_uses — cap on follow-up searches Claude may issue (default 5)
• allowed_domains / blocked_domains — domain filtering
• user_location — { type: "approximate", country?, city?, region?, timezone? }
• max_tokens — output token cap for the synthesized answer (default 4096)
• temperature — sampling temperature, 0–1

web_fetch

Fetches one or more URLs through headless Chrome, extracts the main content as markdown via trafilatura, and optionally distills the result with a pi sub-agent.

Parameters:

• url — single URL to fetch (mutually exclusive with pages)
• prompt — optional extraction prompt. When set, the page content is processed by a fast LLM and only the relevant parts are returned. Omit for the full extracted markdown.
• pages — array of { url, prompt? } (max 10) for concurrent batch fetching with live per-URL progress.

Behavior:

• HTTP URLs are auto-upgraded to HTTPS.
• Cross-host redirects are surfaced rather than followed; make a second call to the redirect target.
• Pages are cached in-memory for 15 minutes — repeated questions about the same page are cheap.
• Pages larger than ~50KB are auto-summarized (when a model is available) to a structured overview when no prompt is provided.
• Browser pool keeps Chrome warm: one shared instance, up to 6 concurrent tabs, idle-shutdown after 60s.
• Stealth mode is enabled by default via puppeteer-extra-plugin-stealth: patches navigator.webdriver, plugins, languages, WebGL vendor, the chrome runtime, and the User-Agent so common bot-detection canaries pass. Pages that refuse to hydrate for headless Chrome (e.g. SPAs behind fingerprinting) render normally. Auth-walled content is still gated by login — stealth doesn't sign you in.
• Two-phase load: navigation waits for domcontentloaded (hard cap 20s), then opportunistically waits up to 5s for the network to quiet down. Heavy ad/analytics traffic no longer prevents a snapshot — if the network never settles within budget, we capture whatever has rendered.

Prerequisites for web_fetch:

• A Python tool runner (auto-detected, in priority order):
  1. uv (uvx) — fastest, recommended
  2. uv run — fallback if uvx alias is missing
  3. pipx — widely available on Debian/Ubuntu
  4. pip-run — niche fallback
• Puppeteer's bundled Chromium is downloaded on first install (~300MB). Set PUPPETEER_EXECUTABLE_PATH to skip the download and use an existing Chrome/Chromium binary.
• puppeteer-extra and puppeteer-extra-plugin-stealth are installed as regular dependencies. They're loaded lazily — if they fail to import the pool falls back to plain puppeteer with a warning.

Auth

Resolved in this order, first hit wins:

1. PI_WIERD_WEB_API_KEY environment variable (explicit override).
2. ctx.modelRegistry.getApiKeyForProvider("anthropic") — covers stored API keys, OAuth refresh-with-locking, and ANTHROPIC_API_KEY via pi's AuthStorage. Same path the agent uses for normal turns, so it inherits any pi.registerProvider("anthropic", { baseUrl }) overrides as long as getApiKeyForProvider reaches them.
3. ANTHROPIC_API_KEY — direct env read, last resort.

OAuth tokens (prefixed sk-ant-oat) are detected automatically and trigger the Claude-Code-stealth header set (anthropic-beta: claude-code-...,oauth-..., User-Agent: claude-cli/..., x-app: cli) plus the "You are Claude Code, ..." system block. claude-3-5-haiku* models skip the Claude Code identity block, matching pi-mono's built-in carve-out.

Install

pi install npm:pi-wierd-web

Restart pi to activate. Verify with /wierd-web status.

Configuration

Settings persist at ~/.pi/agent/wierd-web.json. The file is created on first run, seeded from environment variables. Shape:

{
  "searchModel": "claude-haiku-4-5",
  "fetchModel": "anthropic/claude-haiku-4-5",
  "fetchThinkingLevel": "medium"
}

• searchModel — Anthropic model used by web_search.
• fetchModel — provider/model id for the web_fetch sub-agent. If unset, falls back to the current session model.
• fetchThinkingLevel — thinking level for the web_fetch sub-agent. If unset, falls back to the current session thinking level.

Commands

• /wierd-web status — print models, thinking level, auth source, config path
• /wierd-web model <id> (alias: search-model) — set searchModel
• /wierd-web fetch-model <provider/model-id> — set fetchModel
• /wierd-web fetch-thinking <level> — set fetchThinkingLevel
• /wierd-web reset — wipe config, re-seed from env

CLI flags

• --wierd-web-model <id> — boot-time searchModel override

Environment

• PI_WIERD_WEB_API_KEY — explicit Anthropic credential (API key or OAuth)
• PI_WIERD_WEB_MODEL — default searchModel (falls back to claude-haiku-4-5)
• PI_WIERD_WEB_FETCH_MODEL — default fetchModel for web_fetch
• PI_WIERD_WEB_FETCH_THINKING — default fetchThinkingLevel
• PI_WIERD_WEB_BASE_URL — override the Anthropic base URL (proxies / regional endpoints). Defaults to https://api.anthropic.com.
• PUPPETEER_EXECUTABLE_PATH — use an existing Chrome/Chromium binary instead of puppeteer's bundled download.

Tests

bun --filter pi-wierd-web test

Architecture

File	Responsibility
index.ts	Extension entry: tool registration, /wierd-web command, lifecycle hooks
config.ts	Load/save ~/.pi/agent/wierd-web.json, env seeding
anthropic.ts	Auth resolution, header builder, single POST /v1/messages transport
search.ts	web_search tool definition + response parser + LLM-facing formatter
render.ts	web_search TUI renderers
types.ts	web_search types + minimal raw API content-block shapes
fetch.ts	web_fetch tool definition + cache + pipeline + batch executor
fetch-render.ts	web_fetch TUI renderers (per-URL status, collapsed/expanded result)
fetch-types.ts	web_fetch internal types
browser-pool.ts	Shared puppeteer browser, lazy launch, max-tabs queueing, idle shutdown
extract.ts	Python-runner detection, trafilatura subprocess, timeout helpers
subagent.ts	Spawns pi --mode json sub-agent for distillation/summarization