OPEN SOURCE / MCP SEARCH ROUTER

Web search for agents, with limits you control.

Agent Search MCP starts with eight zero-key sources, searches English and Chinese pages, and returns traceable results within call, time, and evidence budgets.

Install now View on GitHub

Current local capability baseline

ROUTE / FREE_FIRSTREADY

01
QUERYDetect language and request limits
02
FREECall zero-key sources
03
GATECheck results, relevance, and source coverage
04
PACKDeduplicate within the evidence budget

EVIDENCE1200 CHAR BUDGET

8Zero-key sources

Start without an account or search API key

12Search adapters

Free sources plus four optional commercial providers

28.4%Compact token reduction

Measured on the locked bilingual formatting fixture

18.17+Node.js

No browser, database, or Python in the default runtime

01 / ROUTING CONTRACT

Check the evidence before searching again.

The router puts source selection, paid-provider permission, and response size in one request policy. The default free_first mode does not spend configured commercial API credit.

01QUERY
Detect language and request limits
02FREE
Call zero-key sources
03GATE
Check results, relevance, and source coverage
04PACK
Deduplicate within the evidence budget

FREEDefault: free_first → compact evidence

PAIDOptional: quality_escalation → one configured provider

02 / PRODUCT BEHAVIOR

Results include the boundaries that shaped them.

Start without a search account

DuckDuckGo, Sogou, Bing, Baidu, Wikipedia, Startpage, Yandex, and Mojeek work without a search API account.

Paid calls need policy permission

Adding a key does not authorize spend. free_only, free_first, quality_escalation, and paid_first define separate paths.

Token limits belong in the search contract

Result count, snippet length, full-result count, and one evidence budget bound the response while later entries retain their sources.

Failures do not become fake confidence

Relevance, confidence, provider-family count, and partial failures remain separate so an agent can inspect upstream behavior.

Chinese queries stay in Chinese

Sogou and Baidu handle Chinese retrieval directly. The router does not translate an English result set as a substitute.

One core, three access paths

MCP stdio, authenticated Streamable HTTP, and the fasm CLI share the same routing, cache, and evidence contract.

03 / INSTALL

Start with one command.

The default configuration uses only zero-key sources. Connect an MCP client first, then add a commercial provider, HTTP mode, or persistent cache when you need it.

TerminalSTDIO

npx -y agent-search-mcp

MCP client configurationJSON

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

Requires Node.js 18.17 or newer. The default runtime does not require Python.

04 / REPRODUCIBLE EVIDENCE

Token numbers come from a replayable fixture.

The repository replays the same bilingual results with a locked tokenizer and measures only the effect of output formatting.

Output	Average tokens per query	Versus Normal
Normal	2311.0	Baseline
Compact	1655.8	28.4%
Compact+	1607.5	30.4%

05 / FIT

Built for agents that need an inspectable search path.

01Start with free sources and escalate to a commercial provider only after a quality gate
02Search Chinese sources directly instead of translating an English result set
03Cap provider calls, elapsed time, result count, and response context
04Self-host the search entrypoint while retaining sources, failures, and routing decisions

06 / FAQ

Questions to answer before installation.

01Does Agent Search MCP require an API key?

No. Eight sources start without a key. Brave, Tavily, Exa, and You.com run only after you provide credentials and select a routing policy that permits them.

02Can it replace Tavily or Exa?

It fits free-first, self-hosted, and multi-source evidence workflows. Commercial search APIs still have advantages in stability, proprietary indexes, or semantic retrieval, so the project keeps them as controlled escalation paths.

03Does the default runtime need Python?

No. Default search runs on Node.js. Only the optional semantic deduplication and reranking features use Python with Model2Vec.

04How does it reduce agent context use?

Compact output keeps full detail for the first results, turns later results into source-preserving references, and caps query-relevant passages with one evidence budget.

05Is HTTP mode secure by default?

HTTP and both modes require a Bearer token by default. Browser requests with an Origin header must also match the allowlist. stdio remains the simplest local path.

START LOCAL

Run the zero-key path first.

Once connected, your agent can search, extract pages, read Chinese technical sources, and handle every result through the same evidence contract.

Open installation guide Read the product decision record