diff --git a/crates/pyhq/src/client/job.rs b/crates/pyhq/src/client/job.rs
index d2c27e73a..1f08eb9c1 100644
--- a/crates/pyhq/src/client/job.rs
+++ b/crates/pyhq/src/client/job.rs
@@ -14,7 +14,8 @@ use hyperqueue::transfer::messages::{
     TaskKind, TaskKindProgram, TaskSelector, TaskStatusSelector, TaskWithDependencies,
     ToClientMessage,
 };
-use hyperqueue::{rpc_call, tako, JobTaskCount, JobTaskId, Set};
+use hyperqueue::{rpc_call, tako, JobTaskCount, Set};
+use pyo3::exceptions::PyException;
 use pyo3::types::PyTuple;
 use pyo3::{IntoPy, PyAny, PyResult, Python};
 use std::collections::HashMap;
@@ -101,6 +102,12 @@ pub fn submit_job_impl(py: Python, ctx: ClientContextPtr, job: PyJobDescription)
                 // This code is unreachable as long Python cannot submit into open jobs
                 unreachable!()
             }
+            SubmitResponse::NonUniqueTaskId(_) => Err(PyException::new_err(
+                "Non unique IDs in submitted task graph",
+            )),
+            SubmitResponse::InvalidDependencies(_) => {
+                Err(PyException::new_err("Invalid dependency id"))
+            }
         }
     })
 }
@@ -344,11 +351,10 @@ pub fn get_failed_tasks_impl(
             if let Some(job_detail) = job_detail {
                 let mut task_path_map = resolve_task_paths(&job_detail, &response.server_uid);
                 let mut tasks = HashMap::with_capacity(job_detail.tasks.len());
-                for task in job_detail.tasks {
+                for (task_id, task) in job_detail.tasks {
                     match task.state {
                         JobTaskState::Failed { error, .. } => {
-                            let id = task.task_id.as_num();
-                            let path_ctx = task_path_map.remove(&JobTaskId::from(id)).flatten();
+                            let path_ctx = task_path_map.remove(&task_id).flatten();
                             let (stdout, stderr, cwd) = match path_ctx {
                                 Some(paths) => (
                                     stdio_to_string(paths.stdout),
@@ -359,7 +365,7 @@ pub fn get_failed_tasks_impl(
                             };
 
                             tasks.insert(
-                                id,
+                                task_id.as_num(),
                                 FailedTaskContext {
                                     stdout,
                                     stderr,