# iicp-client · Rust SDK
[](https://github.com/RobLe3/iicp-client-rust/actions/workflows/ci.yml)
[](LICENSE)
[](https://iicp.network/spec)
[](https://crates.io/crates/iicp-client)
Official Rust client library for the [IICP protocol](https://iicp.network) — route AI agent tasks by intent across a self-organising mesh of provider nodes. No central broker. No hardcoded endpoints.
```
urn:iicp:intent:llm:chat:v1 → discover → select → submit
```
## Add to Cargo.toml
```toml
[dependencies]
iicp-client = "0.2"
```
Or for the latest unreleased code:
```toml
[dependencies]
iicp-client = { git = "https://github.com/RobLe3/iicp-client-rust" }
```
---
## Quickstart
```rust
use iicp_client::{ChatMessage, ChatOptions, ClientConfig, IicpClient};
#[tokio::main]
async fn main() -> iicp_client::Result<()> {
let client = IicpClient::new(ClientConfig::default())?;
let nodes = client.discover("urn:iicp:intent:llm:chat:v1", None).await?;
let node = nodes.nodes.into_iter().next().expect("no nodes available");
let reply = client.chat(
&node,
vec![
ChatMessage { role: "system".into(), content: "You are a helpful assistant.".into() },
ChatMessage { role: "user".into(), content: "What is IICP?".into() },
],
Some(ChatOptions { timeout_ms: Some(30_000), ..Default::default() }),
).await?;
println!("{}", reply.choices[0].message.content);
Ok(())
}
```
---
## Configuration
```rust
use iicp_client::ClientConfig;
let config = ClientConfig {
directory_url : "https://iicp.network/api".into(), // IICP directory
timeout_ms : 30_000, // max 120 000 (SDK-04)
region : Some("eu-central".into()), // prefer nodes in region
node_token : None, // optional auth token
};
```
| `directory_url` | `"https://iicp.network/api"` | IICP directory endpoint |
| `timeout_ms` | `30000` | Request timeout — max 120 000 ms |
| `region` | `None` | Preferred node region |
| `node_token` | `None` | Bearer token for authenticated nodes |
---
## Discover options
```rust
use iicp_client::DiscoverOptions;
let nodes = client.discover(
"urn:iicp:intent:llm:chat:v1",
Some(DiscoverOptions {
region : Some("eu-central".into()),
model : Some("phi3:mini".into()),
min_reputation: Some(0.7),
limit : Some(5),
}),
).await?;
```
---
## Error handling
```rust
use iicp_client::IicpError;
match client.submit(&node, request).await {
Ok(resp) => println!("{:?}", resp),
Err(IicpError::Protocol { code, message, status }) =>
eprintln!("[{code}] {message} (HTTP {status})"),
Err(e) => eprintln!("Error: {e}"),
}
```
Error codes match the [IICP error reference](https://iicp.network/docs/error-reference).
---
## Serving as a node — handler contract
When you run a serving node (`IicpNode::serve`), your handler returns the **inner result
value**; `serve()` wraps it in the `TaskResponse.result` envelope for you. Do **not** return
an already-wrapped `{"result": ...}` value — that double-nests the response and breaks
cross-flavour interop with the Python/TS SDKs (response shape must be `{"result": {...}}`).
The `backends::invoke_backend` / `openai_compat::invoke` helpers return a
`{"result": ...}` consumer envelope, so when using them as a serve handler, unwrap the
inner value first:
```rust
let v = iicp_client::backends::invoke_backend("openai_compat", &opts, &req.intent, &req.payload)
.await
.unwrap_or_else(|e| serde_json::json!({"error_code": 500, "error_message": e}));
// serve() re-wraps in TaskResponse.result — return the inner value to stay single-level.
Ok(v.get("result").cloned().unwrap_or(v))
```
### Listen port — default 9484, auto-increment (v0.7.5+)
The official IICP port **9484** is the default listen port (`IICP_PORT`, `--port`).
The `iicp-node` binary auto-increments to the next free port when 9484 is already
in use, so several nodes on one host don't need hand-picked ports — first binds
9484, second 9485, third 9486, etc. Each node gets its own port (hence its own NAT
pinhole); multiple models on one node share that single port. Auto-increment is
skipped when you pass an explicit `--public-endpoint`.
---
## NAT traversal — automatic (v0.7.3+)
Since v0.7.3, NAT detection runs automatically on every `iicp-node serve` startup — no flags
needed. Requires the `nat` feature (UPnP detection):
```toml
[dependencies]
iicp-client = { version = "0.7", features = ["nat"] }
# For relay substrate (CGNAT fallback): add "iicp-tcp"
iicp-client = { version = "0.7", features = ["nat", "iicp-tcp"] }
```
| **0** | VPS/cloud (public IP on NIC) or `IICP_PUBLIC_ENDPOINT` set | Registers directly |
| **1a** | Home router with UPnP, no CGNAT | Port-forward via UPnP → register WAN IP |
| **1b** | CGNAT + IPv6 + AddPinhole works | Registers IPv6 with firewall rule |
| **1c** | CGNAT + IPv6 + AddPinhole fails (FRITZ!Box error 606) | Registers IPv6 + logs guidance |
| **3** | CGNAT + no usable IPv6 | Auto-elects relay from directory |
| **4** | Nothing worked | Serves locally with operator guidance |
### Environment-specific behaviour
**Docker bridge (`-p 8020:8020`)** — UPnP is skipped (reaches Docker NAT, not home router).
Set `IICP_PUBLIC_ENDPOINT`:
```bash
docker run -e IICP_PUBLIC_ENDPOINT=http://your-host:8020 \
-e IICP_BACKEND_URL=http://host.docker.internal:11434 \
-p 8020:8020 my-iicp-node
```
**CGNAT + no IPv6 → automatic relay:**
```
[iicp-node] NAT tier=3: auto-electing relay from directory...
[iicp-node] auto-elected relay: relay.example.com:9485
```
### Running a relay-capable node (relay operator)
```rust
use iicp_client::{IicpNode, NodeConfig};
let node = IicpNode::new(NodeConfig {
endpoint : "http://relay.example.com:8020".into(),
intent : "urn:iicp:intent:llm:chat:v1".into(),
relay_capable : true, // accept RELAY_BIND on TCP 9485 (requires iicp-tcp)
relay_accept_port: 9485,
enable_mesh : true, // advertise relay_capable=true in gossip
..Default::default()
});
```
### Opt-out / override
```bash
IICP_AUTO_DETECT_NAT=false # disable detection entirely
IICP_PUBLIC_ENDPOINT=http://x.x.x.x:8020 # trust this endpoint
IICP_RELAY_WORKER_ENDPOINT=host:9485 # specific relay instead of auto-elect
```
---
## SDK conformance
| SDK-01 | discover → select → submit pipeline | ✓ |
| SDK-02 | `task_id` auto-generated (UUID v4) | ✓ |
| SDK-03 | Intent URN pattern validation (regex) | ✓ |
| SDK-04 | `timeout_ms` capped at 120 000 ms | ✓ |
| SDK-05 | Retry on 429 / 503 | planned |
| SDK-06 | W3C `traceparent` propagation | planned |
Conformance tier: `iicp:sdk:v1` (spec S.14) · [Request a badge](https://iicp.network/conformance)
---
## Development
```bash
cargo test # 109 tests
cargo clippy # lint
cargo build --release
cargo run --example quickstart
```
---
## Links
- [Protocol spec](https://iicp.network/spec) — full IICP specification
- [Node setup guide](https://iicp.network/docs/node-setup) — run your own node
- [Error reference](https://iicp.network/docs/error-reference) — all error codes
- [iicp-client-python](https://github.com/RobLe3/iicp-client-python) — Python SDK
- [iicp-client-typescript](https://github.com/RobLe3/iicp-client-typescript) — TypeScript SDK
---
Apache 2.0 · [iicp.network](https://iicp.network)