use rmcp::model::{
ClientCapabilities, ClientJsonRpcMessage, ClientRequest, DiscoverResult, ErrorCode, ErrorData,
JsonRpcRequest, JsonRpcResponse, ProtocolVersion, ServerJsonRpcMessage, ServerResult,
};
use serde_json::json;
#[test]
fn discover_request_deserializes_with_request_meta() {
let message: ClientJsonRpcMessage = serde_json::from_value(json!({
"jsonrpc": "2.0",
"id": 1,
"method": "server/discover",
"params": {
"_meta": {
"io.modelcontextprotocol/protocolVersion": "2026-07-28",
"io.modelcontextprotocol/clientInfo": {
"name": "test-client",
"version": "1.0.0"
},
"io.modelcontextprotocol/clientCapabilities": {}
}
}
}))
.expect("discover request should deserialize");
let ClientJsonRpcMessage::Request(JsonRpcRequest { request, .. }) = message else {
panic!("expected request");
};
let ClientRequest::DiscoverRequest(request) = request else {
panic!("expected discover request");
};
assert_eq!(
request
.extensions
.get::<rmcp::model::RequestMetaObject>()
.and_then(|meta| meta.protocol_version()),
Some(ProtocolVersion::V_2026_07_28)
);
}
#[test]
fn discover_result_deserializes_to_typed_variant() {
let message: ServerJsonRpcMessage = serde_json::from_value(json!({
"jsonrpc": "2.0",
"id": 1,
"result": {
"resultType": "complete",
"supportedVersions": ["2025-11-25", "2026-07-28"],
"capabilities": { "tools": {} },
"serverInfo": {
"name": "test-server",
"version": "1.0.0"
},
"ttlMs": 0,
"cacheScope": "private"
}
}))
.expect("discover result should deserialize");
let ServerJsonRpcMessage::Response(JsonRpcResponse { result, .. }) = message else {
panic!("expected response");
};
let ServerResult::DiscoverResult(DiscoverResult {
supported_versions, ..
}) = result
else {
panic!("expected discover result");
};
assert_eq!(
supported_versions,
vec![ProtocolVersion::V_2025_11_25, ProtocolVersion::V_2026_07_28]
);
}
#[test]
fn discover_result_accepts_server_info_in_namespaced_metadata() {
let message: ServerJsonRpcMessage = serde_json::from_value(json!({
"jsonrpc": "2.0",
"id": 1,
"result": {
"resultType": "complete",
"supportedVersions": ["2026-07-28"],
"capabilities": {},
"ttlMs": 0,
"cacheScope": "private",
"_meta": {
"io.modelcontextprotocol/serverInfo": {
"name": "conformance-mock-server",
"version": "1.0.0"
},
"unrelated": { "preserved": true }
}
}
}))
.expect("discovery response with namespaced server info should deserialize");
let ServerJsonRpcMessage::Response(JsonRpcResponse { result, .. }) = message else {
panic!("expected response");
};
let ServerResult::DiscoverResult(result) = result else {
panic!("expected discovery response, not a tool-call result");
};
let server_info = result.server_info().expect("server info should be present");
assert_eq!(server_info.name, "conformance-mock-server");
assert_eq!(server_info.version, "1.0.0");
let metadata = result.meta.expect("discovery metadata should be preserved");
assert_eq!(
metadata.0.get("io.modelcontextprotocol/serverInfo"),
Some(&json!({
"name": "conformance-mock-server",
"version": "1.0.0"
}))
);
assert_eq!(
metadata.0.get("unrelated"),
Some(&json!({ "preserved": true }))
);
}
#[test]
fn discover_result_serializes_server_info_in_namespaced_metadata() {
let mut result = DiscoverResult::new(
vec![ProtocolVersion::V_2026_07_28],
rmcp::model::ServerCapabilities::default(),
);
result.meta = Some(rmcp::model::MetaObject(
json!({
"io.modelcontextprotocol/serverInfo": {
"name": "stale-server",
"version": "0.1.0"
},
"unrelated": { "preserved": true }
})
.as_object()
.expect("metadata is an object")
.clone(),
));
result.set_server_info(rmcp::model::Implementation::new("test-server", "1.0.0"));
let serialized = serde_json::to_value(result).expect("serialize discovery result");
assert!(serialized.get("serverInfo").is_none());
assert_eq!(
serialized["_meta"]["io.modelcontextprotocol/serverInfo"],
json!({
"name": "test-server",
"version": "1.0.0"
})
);
assert_eq!(
serialized["_meta"]["unrelated"],
json!({ "preserved": true })
);
}
#[test]
fn discover_result_ignores_legacy_top_level_server_info() {
let result: DiscoverResult = serde_json::from_value(json!({
"resultType": "complete",
"supportedVersions": ["2026-07-28"],
"capabilities": {},
"serverInfo": {
"name": "top-level-server",
"version": "2.0.0"
},
"ttlMs": 0,
"cacheScope": "private",
"_meta": {
"io.modelcontextprotocol/serverInfo": {
"name": "metadata-server",
"version": "1.0.0"
},
"unrelated": true
}
}))
.expect("top-level server info should remain supported");
let server_info = result
.server_info()
.expect("namespaced server info is present");
assert_eq!(server_info.name, "metadata-server");
assert_eq!(server_info.version, "1.0.0");
assert_eq!(
result
.meta
.as_ref()
.and_then(|metadata| metadata.0.get("unrelated")),
Some(&json!(true))
);
}
#[test]
fn discover_result_allows_missing_or_malformed_optional_server_info() {
let result = json!({
"resultType": "complete",
"supportedVersions": ["2026-07-28"],
"capabilities": {},
"ttlMs": 0,
"cacheScope": "private",
"_meta": { "unrelated": true }
});
let result =
serde_json::from_value::<DiscoverResult>(result).expect("server info metadata is optional");
assert_eq!(result.server_info(), None);
let malformed_server_info = json!({
"resultType": "complete",
"supportedVersions": ["2026-07-28"],
"capabilities": {},
"ttlMs": 0,
"cacheScope": "private",
"_meta": { "io.modelcontextprotocol/serverInfo": { "name": "missing-version" } }
});
let result = serde_json::from_value::<DiscoverResult>(malformed_server_info)
.expect("opaque metadata should not prevent deserialization");
assert_eq!(result.server_info(), None);
}
#[test]
fn unsupported_protocol_version_error_matches_draft_schema() {
let error = ErrorData::unsupported_protocol_version(
ProtocolVersion::V_2026_07_28,
&[ProtocolVersion::V_2025_11_25],
);
assert_eq!(error.code, ErrorCode::UNSUPPORTED_PROTOCOL_VERSION);
assert_eq!(
error.data,
Some(json!({
"requested": "2026-07-28",
"supported": ["2025-11-25"]
}))
);
}
#[test]
fn missing_required_capability_error_matches_draft_schema() {
let required = ClientCapabilities::builder().enable_elicitation().build();
let error = ErrorData::missing_required_client_capability(required);
assert_eq!(error.code, ErrorCode::MISSING_REQUIRED_CLIENT_CAPABILITY);
assert_eq!(
error.data,
Some(json!({
"requiredCapabilities": {
"elicitation": {}
}
}))
);
}