diff --git a/crates/dips/src/lib.rs b/crates/dips/src/lib.rs
index 2111f3e7f..bd9085232 100644
--- a/crates/dips/src/lib.rs
+++ b/crates/dips/src/lib.rs
@@ -449,6 +449,13 @@ pub async fn validate_and_create_rca(
         return Err(DipsError::UnsupportedNetwork(network_name.to_string()));
     }
 
+    // Resolve chain ID for logging context
+    let chain_id = registry
+        .get_network_by_id(network_name)
+        .map(|n| n.caip2_id.to_string())
+        .or_else(|| additional_networks.get(network_name).cloned())
+        .unwrap_or_else(|| "unknown".to_string());
+
     // Validate price minimums
     let offered_tokens_per_second = terms.tokensPerSecond;
     match price_calculator.get_minimum_price(network_name) {
@@ -456,10 +463,11 @@ pub async fn validate_and_create_rca(
             tracing::info!(
                 agreement_id = %agreement_id,
                 network = %network_name,
+                chain_id = %chain_id,
                 deployment_id = %deployment_id,
-                "offered tokens_per_second '{}' is lower than minimum price '{}'",
-                offered_tokens_per_second,
-                price
+                offered = %offered_tokens_per_second,
+                minimum = %price,
+                "tokens_per_second below minimum, rejecting proposal"
             );
             return Err(DipsError::TokensPerSecondTooLow {
                 network: network_name.to_string(),
@@ -472,9 +480,9 @@ pub async fn validate_and_create_rca(
             tracing::info!(
                 agreement_id = %agreement_id,
                 network = %network_name,
+                chain_id = %chain_id,
                 deployment_id = %deployment_id,
-                "network '{}' is not configured in price calculator",
-                network_name
+                "network not configured in price calculator, rejecting proposal"
             );
             return Err(DipsError::UnsupportedNetwork(network_name.to_string()));
         }
@@ -486,10 +494,11 @@ pub async fn validate_and_create_rca(
         tracing::info!(
             agreement_id = %agreement_id,
             network = %network_name,
+            chain_id = %chain_id,
             deployment_id = %deployment_id,
-            "offered tokens_per_entity_per_second '{}' is lower than minimum price '{}'",
-            offered_entity_price,
-            price_calculator.entity_price()
+            offered = %offered_entity_price,
+            minimum = %price_calculator.entity_price(),
+            "tokens_per_entity_per_second below minimum, rejecting proposal"
         );
         return Err(DipsError::TokensPerEntityPerSecondTooLow {
             minimum: price_calculator.entity_price(),
@@ -621,6 +630,55 @@ mod test {
         assert_eq!(id.as_bytes(), &expected_hash[..16]);
     }
 
+    /// Shared test vector with dipper (dipper-rpc/src/indexer.rs).
+    /// Both repos must produce the same bytes16 for this input.
+    /// If this test fails, the derivation has drifted from the on-chain
+    /// contract and/or from dipper -- cancellations and agreement
+    /// matching will break silently.
+    #[test]
+    fn test_derive_agreement_id_shared_vector() {
+        let rca = RecurringCollectionAgreement {
+            deadline: 1700000300,
+            endsAt: 1700086400,
+            payer: "0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266"
+                .parse()
+                .unwrap(),
+            dataService: "0xCf7Ed3AccA5a467e9e704C703E8D87F634fB0Fc9"
+                .parse()
+                .unwrap(),
+            serviceProvider: "0xf4EF6650E48d099a4972ea5B414daB86e1998Bd3"
+                .parse()
+                .unwrap(),
+            maxInitialTokens: U256::from(1_000_000_000_000_000_000u64),
+            maxOngoingTokensPerSecond: U256::from(1_000_000_000_000_000u64),
+            minSecondsPerCollection: 3600,
+            maxSecondsPerCollection: 86400,
+            nonce: U256::from(0x019d44a86ac97e938672e2501fe630f2u128),
+            metadata: Default::default(),
+        };
+
+        let id = derive_agreement_id(&rca);
+
+        // Pinned expected value. If this fails, check:
+        // 1. dipper: dipper-rpc/src/indexer.rs test_derive_agreement_id_shared_vector
+        // 2. Solidity: RecurringCollector._generateAgreementId()
+        let expected: [u8; 16] = [
+            0x55, 0x79, 0x42, 0xae, 0xfa, 0xb6, 0x16, 0x09, 0xcf, 0xb9, 0xee, 0x14, 0xd3, 0x09,
+            0xa1, 0x7e,
+        ];
+        assert_eq!(
+            id.as_bytes(),
+            &expected,
+            "derive_agreement_id output does not match pinned shared vector. \
+             Actual: 0x{} -- update this test AND the matching test in \
+             dipper (dipper-rpc/src/indexer.rs)",
+            id.as_bytes()
+                .iter()
+                .map(|b| format!("{b:02x}"))
+                .collect::<String>()
+        );
+    }
+
     #[tokio::test]
     async fn test_validate_and_create_rca_success() {
         let payer_signer = PrivateKeySigner::random();