---

Agent Web Search gives an agent two ways to reach the same provider-neutral
search core: a native MCP tool, or a CLI taught through a standard Agent Skill.
Both dispatch enabled providers concurrently, normalize them into one schema,
and isolate provider failures.

Agent ──┬── MCP client ────── web_search ──┐
        │                                  │
        └── Shell + Skill ── CLI command ──┤
                                           ▼
                                      SearchEngine
                                           │
                     DDGS · Exa · Parallel · ARK · Brave
                     Gemini · Grok · Perplexity · Tavily · You.com

Why Agent Web Search

• Concurrent, independent providers. All selected providers run at the same
  time, and one provider's failure never discards another provider's results.
• Zero-key start. The default providers — DDGS, Exa, and Parallel — work
  without any API key.
• Two clean agent integrations. Use MCP for a protocol-native tool, or pair
  the CLI with the included Skill for agents that already have shell access.
• Focused responses. Every provider response contains only a generated
  answer when available and normalized results.
• No telemetry, no shared secrets. Provider keys stay in runtime
  environment variables; there is no shared API-key service.

Providers

Free, keyless defaults: DDGS, Exa, and Parallel all work without an API
key. Exa and Parallel automatically use their free MCP transports until a
paid API key is provided.

Provider	Search backend	API key	Enabled by default
DDGS	DuckDuckGo search	Free · no key required	Yes
Exa	Paid Search API or free MCP fallback	Free without key · optional EXA_API_KEY	Yes
Parallel	Free MCP or paid LLM-optimized search	Free without key · optional PARALLEL_API_KEY	Yes
ARK (Recommended)	Volcengine ARK Responses API + web_search	ARK_API_KEY	No
Brave	Brave Search API	BRAVE_SEARCH_API_KEY	No
Gemini	Google Search grounding	GEMINI_API_KEY	No
Grok	xAI web search and X Search	XAI_API_KEY	No
Perplexity	Native structured Search API	PERPLEXITY_API_KEY	No
Tavily	Tavily Search API	TAVILY_API_KEY	No
You.com	Unified web and news search	YDC_API_KEY	No

The provider architecture is intentionally open: another search-capable
backend can be added without changing the MCP, Hermes, CLI, or Python-facing
interfaces.

Use with an agent

Requirements: Python 3.10+. The default providers — DDGS, Exa, and
Parallel — need no API key. Choose one integration shape for your agent; both
use the same package and search engine. The PyPI package installs both
agent-web-search-mcp and agent-web-search commands.

Option 1: MCP

Choose MCP when the agent supports tool servers and you want typed discovery,
protocol-level errors, or remote access. The same agent-web-search-mcp
command supports local stdio and stateless Streamable HTTP.

Local stdio MCP

Install the package once:

# Recommended isolated installation
pipx install agent-web-search-mcp

# Or install into the active Python environment
python -m pip install agent-web-search-mcp

Then configure the MCP client to launch agent-web-search-mcp:

{
  "mcpServers": {
    "agent-web-search": {
      "command": "agent-web-search-mcp",
      "args": []
    }
  }
}

If uvx is already available, a client can run the package without a
persistent install by using command uvx with args ["agent-web-search-mcp"].

Codex CLI, Claude Code, and OpenCode examples

# Codex CLI
codex mcp add agent-web-search -- agent-web-search-mcp

# Claude Code
claude mcp add agent-web-search -- agent-web-search-mcp

OpenCode:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "agent-web-search": {
      "type": "local",
      "command": ["agent-web-search-mcp"],
      "enabled": true
    }
  }
}

Remote MCP over HTTPS

Use one of the deployment buttons at the top of this README, or run the same
server yourself:

python -c "import secrets; print(secrets.token_urlsafe(32))"
export AGENT_WEB_SEARCH_AUTH_TOKEN="replace-with-the-generated-token"
agent-web-search-mcp --transport http

The server exposes authenticated POST /mcp and public GET /healthz. A
remote MCP client connects like this:

{
  "mcpServers": {
    "agent-web-search": {
      "url": "https://your-deployment.example/mcp",
      "headers": {
        "Authorization": "Bearer your-deployment-token"
      }
    }
  }
}

Every public deployment must set AGENT_WEB_SEARCH_AUTH_TOKEN to at least 32
characters. The server is stateless and does not create MCP-Session-Id values.

Option 2: CLI + Skill

Choose this shape when the agent already has shell access and supports Agent
Skills. The Skill teaches the agent how to invoke the CLI, select controls,
interpret results, and handle structured failures; no MCP configuration is
needed.

1. Install the CLI:

   pipx install agent-web-search-mcp
   # Or: python -m pip install agent-web-search-mcp
   

2. Install the included agent-web-search Skill:

   npx skills add JerryLiu369/agent-web-search --skill agent-web-search
   

   If the agent does not use the skills installer, copy
   skills/agent-web-search into that client's Skills directory.

3. Verify the CLI, then let the agent search:

   agent-web-search --version
   agent-web-search "What changed in the latest OpenAI Codex CLI?"
   

The CLI writes one JSON document to stdout on success. If every provider fails,
it writes the shared all_providers_failed JSON to stderr and exits with status
1, so shell-capable agents can distinguish a real failure from empty results.

CLI option	MCP argument	Values	Default
positional QUERY	query	natural-language question	required
--provider (repeatable)	providers	enabled provider names	all enabled
--max-results	max_results	1–20	10
--max-keyword	max_keyword	1–10	3
--time-range	time_range	d, w, m, y	—
--grok-search-mode	grok_search_mode	web_search, x_search, both	web_search

Install the latest development version from GitHub

pipx install 'git+https://github.com/JerryLiu369/agent-web-search.git'

[!IMPORTANT]
Do not place API keys in shell history, source code, Git commits, screenshots,
or checked-in MCP configuration. Supply them through server-side or local
environment variables.

Shared request and response

MCP exposes one tool named web_search; the CLI maps to the same inputs.

Argument	Type	Required	Default	Description
query	string	Yes	—	Complete natural-language search question
max_results	integer, 1–20	No	10	Desired maximum number of results
max_keyword	integer, 1–10	No	3	Desired maximum number of search queries or keywords
time_range	d, w, m, y	No	—	Past day, week, month, or year
providers	string array	No	All enabled	Narrow the request to enabled providers
grok_search_mode	web_search, x_search, both	No	web_search	Available only when Grok is enabled

Example call:

{
  "query": "GPU kernel generation papers from the past month",
  "max_results": 5,
  "time_range": "m",
  "providers": ["ddgs", "exa"]
}

Provider selection has two levels:

1. AGENT_WEB_SEARCH_PROVIDERS defines the provider set when the process starts.
2. The request-level providers argument may narrow that set, but cannot enable
   a provider that was disabled at startup.

Response format

Each selected provider that succeeds appears under providers; failed
providers are omitted:

{
  "query": "GPU kernel generation papers from the past month",
  "providers": {
    "ddgs": {
      "results": [
        {
          "title": "Example result",
          "url": "https://example.com/paper",
          "description": "Excerpt of the matching page",
          "published_at": "2026-08-02"
        }
      ]
    }
  }
}

Field	Meaning
answer	Provider-generated prose answer, when the backend produces one; omitted otherwise
results	Result rows: title, url, description, plus optional published_at and author

If every selected provider fails, MCP returns a tool error. The CLI writes the
same payload to stderr and exits with status 1. Both use the stable code
all_providers_failed and include per-provider diagnostics:

{
  "error": {
    "code": "all_providers_failed",
    "message": "All enabled search providers failed. Check provider configuration, credentials, quotas, and network access.",
    "provider_errors": {
      "ddgs": "RuntimeError: rate limited"
    }
  },
  "query": "GPU kernel generation papers from the past month"
}

Python API

The CLI, MCP servers, and Hermes plugin are thin wrappers around
agent_web_search.SearchEngine, which is the public Python API.
SearchRequest accepts the same fields as the MCP tool arguments:

from agent_web_search import SearchEngine, SearchRequest

engine = SearchEngine()  # reads AGENT_WEB_SEARCH_* variables at construction

response = engine.search(
    SearchRequest(query="latest MCP spec changes", max_results=5, time_range="m")
)

for name, provider in response.providers.items():
    print(f"{name}: searched={provider.searched}, results={len(provider.results)}")

if response.all_providers_failed:
    print(response.failed_provider_errors)

Configuration

Configuration is read from environment variables when the CLI, MCP server, or
Hermes plugin starts. Restart the process after changing provider settings.
See .env.example for a commented template of every variable.

General settings

Variable	Default	Purpose
AGENT_WEB_SEARCH_PROVIDERS	ddgs,exa,parallel	Comma-separated startup-enabled provider set
AGENT_WEB_SEARCH_TIMEOUT	60	Socket timeout for a single upstream HTTP call. Multi-step providers multiply it: keyless Parallel makes up to 3 calls (worst case 3×), ARK may append a continuation call (worst case 2×), so the whole search can take up to 3 × this value

Example:

export AGENT_WEB_SEARCH_PROVIDERS="ddgs,exa,brave"
export AGENT_WEB_SEARCH_TIMEOUT="30"

$env:AGENT_WEB_SEARCH_PROVIDERS = "ddgs,exa,brave"
$env:AGENT_WEB_SEARCH_TIMEOUT = "30"

HTTP transport settings

Variable	Default	Purpose
AGENT_WEB_SEARCH_MCP_TRANSPORT	stdio	stdio or http; --transport may override it
AGENT_WEB_SEARCH_HTTP_HOST	0.0.0.0	HTTP bind host for container deployments
AGENT_WEB_SEARCH_HTTP_PORT	PORT or 8000	HTTP bind port; explicit value overrides platform PORT
AGENT_WEB_SEARCH_AUTH_TOKEN	—	Required HTTP Bearer Token, at least 32 characters
AGENT_WEB_SEARCH_ALLOW_ANONYMOUS	false	Explicitly disables HTTP auth for trusted/demo environments
AGENT_WEB_SEARCH_HTTP_ALLOWED_HOSTS	—	Optional comma-separated Host allowlist
AGENT_WEB_SEARCH_HTTP_ALLOWED_ORIGINS	—	Optional comma-separated Origin allowlist; requires allowed hosts
AGENT_WEB_SEARCH_HTTP_LOG_LEVEL	info	Uvicorn log level for the container server

HTTP settings remain environment-only; the deployment files do not introduce
a second application configuration format.

Provider settings

Default providers are listed first; optional providers then follow alphabetical
order.

1. DDGS

DDGS uses DuckDuckGo and requires no API key or provider-specific environment
variables. The ddgs Python dependency is installed with the package.

2. Exa

Exa supports both paid and keyless modes.

Variable	Required	Purpose
EXA_API_KEY	No	Uses the paid Search API when present
EXA_MCP_URL	No	Overrides the free MCP endpoint when no API key is set

Without EXA_API_KEY, Exa falls back to its free MCP endpoint on a best-effort
basis. The paid API generally provides higher quota and reliability.

3. Parallel

Parallel returns information-dense excerpts ranked for LLM context. One
parallel provider automatically selects its transport:

• Without a key, it uses Parallel's free Search MCP.
• With PARALLEL_API_KEY, it uses the paid Search REST API.

Both transports map excerpts into the common result description, so the
calling agent does not need to distinguish parallel-free from parallel.

Variable	Required	Purpose
PARALLEL_API_KEY	No	Enables the paid API; omit it to use the free MCP

Parallel is enabled by default and its key is optional.

4. ARK (Recommended)

Volcengine ARK uses model-backed search grounding through the Responses API.
Add ark to AGENT_WEB_SEARCH_PROVIDERS after providing the key.

Variable	Required	Purpose
ARK_API_KEY	Yes	One key, or multiple comma/newline-separated keys
AGENT_WEB_SEARCH_ARK_MODELS	No	Comma/newline-separated ARK model IDs

One model stays fixed; multiple models are selected round-robin for successive
requests. When multiple ARK keys are configured, a key is selected per request.

Optional Volcengine collaboration rewards information

Agent Web Search does not require participation in a rewards program. ARK users
may optionally review the official
Volcengine Collaboration Rewards Program.
Quota, supported models, validity periods, and data-authorization terms can
change. Check the official terms before opting in. Participation is not
required to use Agent Web Search.

5. Brave

Variable	Required	Purpose
BRAVE_SEARCH_API_KEY	Yes	Brave Web Search API credential

Add brave to AGENT_WEB_SEARCH_PROVIDERS after providing the key.

6. Gemini

Variable	Required	Purpose
GEMINI_API_KEY	Yes	Google AI API credential
AGENT_WEB_SEARCH_GEMINI_MODELS	No	Comma/newline-separated Gemini model IDs

Gemini maps common result and time controls into best-effort prompt
constraints. One configured model stays fixed; multiple models are selected
round-robin for successive requests.

7. Grok

Variable	Required	Purpose
XAI_API_KEY	Yes	xAI API credential
AGENT_WEB_SEARCH_GROK_MODELS	No	Comma/newline-separated Grok model IDs

One configured model stays fixed; multiple models are selected round-robin for
successive requests.

When Grok is enabled, the public tool schema adds grok_search_mode:

• web_search searches the web.
• x_search searches X with native date filters when available.
• both exposes both server-side tools in one request and lets Grok choose; it
  does not issue two independent model requests.

8. Perplexity

This provider uses Perplexity's native structured Search API. It returns result
rows rather than a Sonar-generated prose answer; OpenRouter compatibility is
intentionally outside this provider's scope.

Variable	Required	Purpose
PERPLEXITY_API_KEY	Yes	Perplexity Search API credential

Add perplexity to AGENT_WEB_SEARCH_PROVIDERS after providing the key.

9. Tavily

Variable	Required	Purpose
TAVILY_API_KEY	Yes	Tavily Search API credential

Add tavily to AGENT_WEB_SEARCH_PROVIDERS after providing the key.

10. You.com

You.com returns unified web and news sections. Agent Web Search merges both,
deduplicates URLs, and applies max_results to the combined result list.

Variable	Required	Purpose
YDC_API_KEY	Yes	You.com Search API credential

Add you to AGENT_WEB_SEARCH_PROVIDERS after providing the key.

Common search controls

Each provider maps the shared controls to its native API when possible and
ignores unsupported controls.

Provider	max_results	max_keyword	time_range
DDGS	Native max_results	Ignored	Native timelimit
Exa	Native result count	Ignored	Native publish date
Parallel	REST: native max_results; keyless MCP: client-side truncation (results[:max_results])	Ignored	Ignored
ARK	Native limit	Native	Prompt constraint
Brave	Native count	Ignored	Native freshness
Gemini	Prompt constraint	Prompt constraint	Prompt constraint
Grok	Prompt constraint	Prompt constraint	Prompt; X Search also uses native dates
Perplexity	Native max_results	Ignored	Native recency filter
Tavily	Native max_results	Ignored	Native time_range
You.com	Native count, combined cap	Ignored	Native freshness

Prompt-based controls are best-effort and are not strict guarantees.

Other interfaces

Native Hermes plugin

Install the native plugin directly from GitHub:

pip install 'ddgs>=9.0'
hermes plugins install JerryLiu369/agent-web-search --no-enable
hermes plugins enable agent-web-search --allow-tool-override

The plugin intentionally replaces Hermes' built-in web_search tool, so the
explicit --allow-tool-override grant is required. Start a new Hermes session
after enabling it; restart the gateway when using a messaging channel.

Hermes can also connect through its generic MCP integration instead of the
native plugin.

Troubleshooting

• all_providers_failed — every selected provider errored. MCP marks the
  call as an error; the CLI writes diagnostics to stderr and exits 1. Check
  keys, quotas, and network access. A single retry may help a transient limit.
• agent-web-search is not found — install the PyPI package with pipx or
  pip, then start a new shell so its scripts directory is on PATH.
• HTTP 401 invalid_token — the Authorization: Bearer … header must
  match AGENT_WEB_SEARCH_AUTH_TOKEN, which must be at least 32 characters.
• A provider is missing from a response — failed providers are omitted
  from successful responses. The Python API exposes the reasons in
  response.failed_provider_errors.
• Provider changes have no effect — provider settings are read once at
  startup; restart the CLI, MCP server, or Hermes plugin after changing them.
• MCP client times out before the tool returns —
  AGENT_WEB_SEARCH_TIMEOUT bounds a single upstream HTTP call, not the
  whole search. Keyless Parallel issues up to 3 calls and ARK may append a
  continuation request, so the worst case is 3 × AGENT_WEB_SEARCH_TIMEOUT;
  configure your MCP client's tool timeout accordingly.

Development

Using uv keeps the development environment
isolated and reproducible:

git clone https://github.com/JerryLiu369/agent-web-search.git
cd agent-web-search
uv venv
uv pip install -e '.[dev]'
uv run pytest -q
uv run ruff check .

Standard venv + pip alternative

python -m venv .venv
# Linux/macOS: source .venv/bin/activate
# Windows PowerShell: .venv\Scripts\Activate.ps1
python -m pip install -e '.[dev]'
pytest -q
ruff check .

ARCHITECTURE.md is the design source of truth, and
AGENTS.md lists the non-negotiable invariants. Read both before
changing transports, configuration, authentication, deployment, providers, or
tool schemas, keep stdio and HTTP behavior identical, and keep pytest and
ruff green in the same change.

License

MIT