diff --git a/README.md b/README.md
index 46eaca4..ceda8e9 100644
--- a/README.md
+++ b/README.md
@@ -41,8 +41,9 @@ Auto-selection tries them in this order:
 - **OpenRouter** (`OPENROUTER_API_KEY`, begins `sk-or-`): maps `jev-latest` to `typesafe/jev-1.13`.
 - **Cloudflare** (`JEV_CLOUDFLARE_API_TOKEN` preferred over `CLOUDFLARE_API_TOKEN`, plus `CLOUDFLARE_ACCOUNT_ID`): maps `jev-latest` to `typesafe/jev`.
 - **Vercel AI Gateway** (`AI_GATEWAY_API_KEY`): selects `typesafe-ai/jev` unless given a `typesafe-ai/` model.
+- **SiliconFlow** (`SILICONFLOW_API_KEY`): maps `jev-latest` to `semif`, the always-current alias on its System One endpoint.
 
-Set `JEV_PROVIDER` to `typesafe`, `openrouter`, `cloudflare`, `vercel`, or `auto` to select strictly. Unknown names and missing credentials fail rather than falling through. With no provider configured, the diagnostic names every supported credential variable. `config.env` accepts an injectable environment record, and `config.transport` accepts a run-bound transport for callers that own one.
+Set `JEV_PROVIDER` to `typesafe`, `openrouter`, `cloudflare`, `vercel`, `siliconflow`, or `auto` to select strictly. Unknown names and missing credentials fail rather than falling through. With no provider configured, the diagnostic names every supported credential variable. `config.env` accepts an injectable environment record, and `config.transport` accepts a run-bound transport for callers that own one.
 
 ## Validation
 
@@ -50,7 +51,7 @@ Every reply is checked before you see it. Validation requires exactly the reques
 
 ## Adding a provider
 
-The built-ins stay limited to major, well-known providers. TypeSafe, OpenRouter, Cloudflare, and Vercel are in. Pull requests for other major providers are welcome; small or regional carriers are not merged as built-ins. They have two supported paths below, and good third-party packages get linked from the READMEs of this package, [jev-browser](https://github.com/jkudish/jev-browser), and [jev-mcp](https://github.com/jkudish/jev-mcp).
+The built-ins stay limited to major, well-known providers. TypeSafe, OpenRouter, Cloudflare, Vercel, and SiliconFlow are in. Pull requests for other major providers are welcome; small or regional carriers are not merged as built-ins. They have two supported paths below, and good third-party packages get linked from the READMEs of this package, [jev-browser](https://github.com/jkudish/jev-browser), and [jev-mcp](https://github.com/jkudish/jev-mcp).
 
 ### No code: inject a transport
 
diff --git a/src/provider.ts b/src/provider.ts
index b6a9fb2..b231425 100644
--- a/src/provider.ts
+++ b/src/provider.ts
@@ -2,6 +2,7 @@ import { typesafe } from "./transports/typesafe.js";
 import { openrouter } from "./transports/openrouter.js";
 import { cloudflare } from "./transports/cloudflare.js";
 import { vercel } from "./transports/vercel.js";
+import { siliconflow } from "./transports/siliconflow.js";
 
 export interface JevTransportInput {
   state: unknown;
@@ -22,7 +23,7 @@ export interface JevTransport {
 }
 
 export interface BuiltinDriver {
-  readonly name: "typesafe" | "openrouter" | "cloudflare" | "vercel";
+  readonly name: "typesafe" | "openrouter" | "cloudflare" | "vercel" | "siliconflow";
   isConfigured(env: Env): boolean;
   assertConfigured(env: Env): void;
   create(env: Env): JevTransport;
@@ -43,13 +44,13 @@ export type AskResult =
 
 export interface AskConfig { env?: Env; transport?: JevTransport }
 
-const drivers: readonly BuiltinDriver[] = [typesafe, openrouter, cloudflare, vercel];
+const drivers: readonly BuiltinDriver[] = [typesafe, openrouter, cloudflare, vercel, siliconflow];
 
 export function resolveTransport(env: Env = process.env): JevTransport {
   const explicit = (env.JEV_PROVIDER ?? "auto").toLowerCase();
   if (explicit !== "auto") {
     const driver = drivers.find((candidate) => candidate.name === explicit);
-    if (!driver) throw new Error("Unknown JEV_PROVIDER; choose typesafe, openrouter, cloudflare, vercel, or auto.");
+    if (!driver) throw new Error("Unknown JEV_PROVIDER; choose typesafe, openrouter, cloudflare, vercel, siliconflow, or auto.");
     try {
       driver.assertConfigured(env);
     } catch (error) {
@@ -59,7 +60,7 @@ export function resolveTransport(env: Env = process.env): JevTransport {
   }
   const driver = drivers.find((candidate) => candidate.isConfigured(env));
   if (!driver) {
-    throw new Error("No TYPESAFE_API_KEY, OPENROUTER_API_KEY (sk-or-), Cloudflare token (CLOUDFLARE_API_TOKEN or JEV_CLOUDFLARE_API_TOKEN) + CLOUDFLARE_ACCOUNT_ID, or AI_GATEWAY_API_KEY found. Set one, or JEV_PROVIDER to choose explicitly.");
+    throw new Error("No TYPESAFE_API_KEY, OPENROUTER_API_KEY (sk-or-), Cloudflare token (CLOUDFLARE_API_TOKEN or JEV_CLOUDFLARE_API_TOKEN) + CLOUDFLARE_ACCOUNT_ID, AI_GATEWAY_API_KEY, or SILICONFLOW_API_KEY found. Set one, or JEV_PROVIDER to choose explicitly.");
   }
   return driver.create(env);
 }
@@ -108,7 +109,7 @@ export async function ask(input: JevTransportInput, config: AskConfig = {}): Pro
     return { ok: false, code: "configuration_error", message };
   }
   // Injected transport names are untrusted and never included in error text.
-  const provider = typeof transport.name === "string" && /^(typesafe|openrouter|cloudflare|vercel|fixture)$/.test(transport.name) ? transport.name : "unknown";
+  const provider = typeof transport.name === "string" && /^(typesafe|openrouter|cloudflare|vercel|siliconflow|fixture)$/.test(transport.name) ? transport.name : "unknown";
   let reply: JevTransportReply;
   try {
     reply = await transport.ask(input);
diff --git a/src/transports/siliconflow.ts b/src/transports/siliconflow.ts
new file mode 100644
index 0000000..e346017
--- /dev/null
+++ b/src/transports/siliconflow.ts
@@ -0,0 +1,53 @@
+import type { BuiltinDriver } from "../provider.js";
+
+export const siliconflow: BuiltinDriver = {
+  name: "siliconflow",
+  isConfigured: (env) => Boolean(env.SILICONFLOW_API_KEY),
+  assertConfigured(env) {
+    if (!this.isConfigured(env)) throw new Error("SILICONFLOW_API_KEY is not set.");
+  },
+  create(env) {
+    this.assertConfigured(env);
+    const key = env.SILICONFLOW_API_KEY!;
+    return {
+      name: this.name,
+      async ask({ state, questions, model, signal }) {
+        const effective = model === "jev-latest" ? "semif" : model;
+        const response = await fetch("https://api.siliconflow.cn/v1/systemone", {
+          method: "POST",
+          headers: { Authorization: `Bearer ${key}`, "Content-Type": "application/json" },
+          body: JSON.stringify({ model: effective, state, questions }),
+          signal,
+        }).catch(() => {
+          if (signal.aborted) throw signal.reason;
+          throw new Error("SiliconFlow system one API HTTP unavailable (network error; 0 response bytes)");
+        });
+        const raw = await response.text().catch(() => {
+          if (signal.aborted) throw signal.reason;
+          throw new Error(`SiliconFlow system one API HTTP ${response.status} (body read error; 0 response bytes)`);
+        });
+        const bytes = Buffer.byteLength(raw);
+        if (!response.ok) throw new Error(`SiliconFlow system one API HTTP ${response.status} (request failed; ${bytes} response bytes)`);
+        let body: any;
+        try {
+          body = JSON.parse(raw);
+        } catch {
+          throw new Error(`SiliconFlow system one API HTTP ${response.status} (invalid JSON; ${bytes} response bytes)`);
+        }
+        if (!body || typeof body !== "object" || Array.isArray(body)) throw new Error(`SiliconFlow system one API HTTP ${response.status} (invalid envelope; ${bytes} response bytes)`);
+        const usage = body.usage;
+        if (usage !== undefined && (typeof usage !== "object" || usage === null || Array.isArray(usage))) {
+          throw new Error(`SiliconFlow system one API HTTP ${response.status} (invalid usage; ${bytes} response bytes)`);
+        }
+        return {
+          answers: body.answers,
+          usage: {
+            input_tokens: usage && Object.hasOwn(usage, "input_tokens") ? usage.input_tokens : 0,
+            output_tokens: usage && Object.hasOwn(usage, "output_tokens") ? usage.output_tokens : 0,
+          },
+          model: typeof body.model === "string" && body.model ? body.model : effective,
+        };
+      },
+    };
+  },
+};
diff --git a/test/transports.test.mjs b/test/transports.test.mjs
index 2159cf1..9266892 100644
--- a/test/transports.test.mjs
+++ b/test/transports.test.mjs
@@ -4,6 +4,7 @@ import { ask, resolveTransport } from "../dist/index.js";
 import { typesafe } from "../dist/transports/typesafe.js";
 import { openrouter } from "../dist/transports/openrouter.js";
 import { cloudflare } from "../dist/transports/cloudflare.js";
+import { siliconflow } from "../dist/transports/siliconflow.js";
 import { createVercelDriver, adaptVercelAnswers } from "../dist/transports/vercel.js";
 
 const askJev = (transport, input) => ask(input, { transport });
@@ -11,7 +12,7 @@ const rejected = (result, code, pattern) => {
   assert.equal(result.ok, false);
   assert.equal(result.code, code);
   assert.match(result.message, pattern);
-  assert.doesNotMatch(result.message, /body-secret|ts-secret|sk-or-secret|high-secret|low-secret|ai-secret/);
+  assert.doesNotMatch(result.message, /body-secret|ts-secret|sk-or-secret|high-secret|low-secret|ai-secret|sf-secret/);
 };
 
 const signal = new AbortController().signal;
@@ -28,30 +29,31 @@ async function withFetch(fn, run) {
 }
 
 test("registry auto-detects in precedence order and explicit names select only themselves", () => {
-  const all = { TYPESAFE_API_KEY: "ts-secret", OPENROUTER_API_KEY: "sk-or-secret", CLOUDFLARE_API_TOKEN: "cf-secret", CLOUDFLARE_ACCOUNT_ID: "account", AI_GATEWAY_API_KEY: "ai-secret" };
+  const all = { TYPESAFE_API_KEY: "ts-secret", OPENROUTER_API_KEY: "sk-or-secret", CLOUDFLARE_API_TOKEN: "cf-secret", CLOUDFLARE_ACCOUNT_ID: "account", AI_GATEWAY_API_KEY: "ai-secret", SILICONFLOW_API_KEY: "sf-secret" };
   for (const [removed, expected] of [
     [[], "typesafe"],
     [["TYPESAFE_API_KEY"], "openrouter"],
     [["TYPESAFE_API_KEY", "OPENROUTER_API_KEY"], "cloudflare"],
     [["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN"], "vercel"],
+    [["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN", "AI_GATEWAY_API_KEY"], "siliconflow"],
   ]) {
     const env = { ...all };
     for (const key of removed) delete env[key];
     assert.equal(resolveTransport(env).name, expected);
   }
-  for (const name of ["typesafe", "openrouter", "cloudflare", "vercel"]) {
+  for (const name of ["typesafe", "openrouter", "cloudflare", "vercel", "siliconflow"]) {
     assert.equal(resolveTransport({ ...all, JEV_PROVIDER: name.toUpperCase() }).name, name);
   }
   assert.equal(resolveTransport({ JEV_CLOUDFLARE_API_TOKEN: "pref", CLOUDFLARE_ACCOUNT_ID: "account" }).name, "cloudflare");
   assert.throws(() => resolveTransport({ ...all, JEV_PROVIDER: "typo" }), /Unknown JEV_PROVIDER/);
-  assert.throws(() => resolveTransport({}), (error) => ["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN", "JEV_CLOUDFLARE_API_TOKEN", "CLOUDFLARE_ACCOUNT_ID", "AI_GATEWAY_API_KEY"].every((name) => error.message.includes(name)));
+  assert.throws(() => resolveTransport({}), (error) => ["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN", "JEV_CLOUDFLARE_API_TOKEN", "CLOUDFLARE_ACCOUNT_ID", "AI_GATEWAY_API_KEY", "SILICONFLOW_API_KEY"].every((name) => error.message.includes(name)));
 });
 
 test("public ask returns configuration errors and redacts thrown transport details", async () => {
   rejected(await ask(input, { env: { JEV_PROVIDER: "typo" } }), "configuration_error", /Unknown JEV_PROVIDER/);
   const absent = await ask(input, { env: {} });
   rejected(absent, "configuration_error", /No TYPESAFE_API_KEY/);
-  for (const name of ["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN", "JEV_CLOUDFLARE_API_TOKEN", "CLOUDFLARE_ACCOUNT_ID", "AI_GATEWAY_API_KEY"]) {
+  for (const name of ["TYPESAFE_API_KEY", "OPENROUTER_API_KEY", "CLOUDFLARE_API_TOKEN", "JEV_CLOUDFLARE_API_TOKEN", "CLOUDFLARE_ACCOUNT_ID", "AI_GATEWAY_API_KEY", "SILICONFLOW_API_KEY"]) {
     assert.ok(absent.message.includes(name));
   }
   rejected(await ask(input, { transport: { name: "body-secret", ask: async () => { throw Error("body-secret ts-secret"); } } }), "request_failed", /provider unknown: request failed/);
@@ -67,6 +69,7 @@ test("forced credentials reject every missing or invalid variant without leaking
     ["cloudflare", { CLOUDFLARE_ACCOUNT_ID: "account-secret" }, /CLOUDFLARE_API_TOKEN/],
     ["cloudflare", { JEV_CLOUDFLARE_API_TOKEN: "cf-secret" }, /CLOUDFLARE_ACCOUNT_ID/],
     ["vercel", {}, /AI_GATEWAY_API_KEY/],
+    ["siliconflow", {}, /SILICONFLOW_API_KEY/],
   ];
   for (const [name, env, pattern] of cases) {
     assert.throws(() => resolveTransport({ ...env, JEV_PROVIDER: name }), (error) => {
@@ -257,6 +260,36 @@ test("Cloudflare token priority, double envelope, state, usage, and safe errors"
   });
 });
 
+test("SiliconFlow maps latest to semif, sends exact envelope and redacts HTTP errors", async () => {
+  const calls = [];
+  await withFetch(async (url, init) => {
+    calls.push({ url, init });
+    return Response.json({ answers, usage, model: JSON.parse(init.body).model });
+  }, async () => {
+    const transport = siliconflow.create({ SILICONFLOW_API_KEY: "sf-secret" });
+    assert.equal((await askJev(transport, input)).model, "semif");
+    assert.equal((await askJev(transport, { ...input, model: "diffusiongemma" })).model, "diffusiongemma");
+    assert.equal((await transport.ask({ ...input, model: "kev-4b" })).model, "kev-4b");
+    assert.equal(calls[0].url, "https://api.siliconflow.cn/v1/systemone");
+    assert.equal(calls[0].init.method, "POST");
+    assert.deepEqual(calls[0].init.headers, { Authorization: "Bearer sf-secret", "Content-Type": "application/json" });
+    assert.equal(calls[0].init.signal, signal);
+    assert.deepEqual(JSON.parse(calls[0].init.body), { model: "semif", state: input.state, questions });
+    assert.deepEqual(JSON.parse(calls[2].init.body).model, "kev-4b");
+  });
+  for (const response of [new Response("body-secret", { status: 401 }), new Response("body-secret", { status: 200 })]) {
+    await withFetch(async () => response, async () => {
+      rejected(await askJev(siliconflow.create({ SILICONFLOW_API_KEY: "sf-secret" }), input), "request_failed", /request failed/);
+    });
+  }
+  await withFetch(async () => Response.json({ usage }), async () => {
+    rejected(await askJev(siliconflow.create({ SILICONFLOW_API_KEY: "sf-secret" }), input), "malformed_answer", /question <response>.*answers/);
+  });
+  await withFetch(async () => { throw new Error("body-secret sf-secret"); }, async () => {
+    rejected(await askJev(siliconflow.create({ SILICONFLOW_API_KEY: "sf-secret" }), input), "request_failed", /request failed/);
+  });
+});
+
 test("Vercel factory forwards evaluate request and pure adaptation preserves confidence", async () => {
   let call;
   const raw = { item: { type: "choice", choice: "beta", probabilities: { alpha: 0.2, beta: 0.8 } }, yes: { type: "boolean", probability: 0.7 } };
@@ -305,6 +338,7 @@ test("all adapters distinguish absent usage from malformed containers and presen
     ["openrouter", "input_tokens", (wire) => withFetch(async () => Response.json({ answers, ...wire }), () => askJev(openrouter.create({ OPENROUTER_API_KEY: "sk-or-secret" }), input))],
     ["cloudflare", "input_tokens", (wire) => withFetch(async () => Response.json({ result: { state: "Completed", result: { answers, ...wire } } }), () => askJev(cloudflare.create({ CLOUDFLARE_API_TOKEN: "cf-secret", CLOUDFLARE_ACCOUNT_ID: "account" }), input))],
     ["vercel", "inputTokens", (wire) => askJev(createVercelDriver(async () => ({ answers: vercelAnswers, ...wire })).create({ AI_GATEWAY_API_KEY: "ai-secret" }), input)],
+    ["siliconflow", "input_tokens", (wire) => withFetch(async () => Response.json({ answers, ...wire }), () => askJev(siliconflow.create({ SILICONFLOW_API_KEY: "sf-secret" }), input))],
   ]) {
     assert.deepEqual((await run({})).usage, { input_tokens: 0, output_tokens: 0 }, name);
     assert.deepEqual((await run({ usage: {} })).usage, { input_tokens: 0, output_tokens: 0 }, name);