Specify Txn-Token is only in Request and always has one token

Author: tulshi

draft-ietf-oauth-transaction-tokens.md

@@ -650,7 +650,7 @@ Examples of public-key based authentication include those defined in OAuth 2.0 M
 Txn-Tokens need to be communicated between workloads that depend upon them to authorize the request. Such workloads will often present HTTP {{RFC9110}} interfaces for being invoked by other workloads. This section specifies the HTTP header the invoking workload MUST use to communicate the Txn-Token to the invoked workload, when the invoked workload presents an HTTP interface. Note that the standard HTTP `Authorization` header MUST NOT be used because that may be used by the workloads to communicate channel authorization.
 
 ## Txn-Token HTTP Header {#txn-token-http-header}
-A workload that invokes another workload using HTTP and needs to present a Txn-Token to the invoked workload MUST use the HTTP Header `Txn-Token` to communicate the Txn-Token. The value of this header MUST be the Txn-Token.
+A workload that invokes another workload using HTTP and needs to present a Txn-Token to the invoked workload MUST use the HTTP Header `Txn-Token` to communicate the Txn-Token in the HTTP Request. The value of this header MUST be exactly one Txn-Token.
 
 # Security Considerations {#Security}