Diagnostics

Immediate.Jobs currently uses one zero-padded diagnostic sequence. The analyzer package exposes the following IDs; method-shape, partial and other handler diagnostics come from Immediate.Handlers separately.

ID	Severity	Trigger and location	Fix
IJOB0001	Error	A [Job] type lacks [Handler]; job declaration.	Add Immediate.Handlers [Handler].
IJOB0002	Error	Two jobs derive/configure the same persisted name; each conflicting type.	Give every job a unique stable Name.
IJOB0003	Error	Two queue definitions derive/configure the same persisted name; each conflicting type.	Give every queue a unique stable Name.
IJOB0004	Error	The compilation references NodaTime but not Immediate.Jobs.NodaTime; compilation-wide, no source location.	Add the companion package, or remove the NodaTime reference.
IJOB0005	Error	Invalid attempts, concurrency, enum, timeout or backoff configuration; [Job].	Use defined enums, positive attempts/backoff/timeout and non-negative concurrency.
IJOB0006	Error	A cron job has a payload other than EmptyJobRequest; job type.	Make it payloadless or remove Cron.
IJOB0007	Error	Invalid five/six-field cron or blank cron time zone; [Job].	Correct Cron and use a non-blank time-zone ID.
IJOB0008	Error	Explicit/derived job name contains no letter or digit; job type.	Rename the class or set a usable Name.
IJOB0009	Error	[UsesQueue<T>] points to a type without [QueueDefinition]; attribute.	Mark T as a queue definition or select the correct type.
IJOB0010	Warning	One class carries both [Job] and [QueueDefinition]; both attributes.	Split the job and queue definition into separate types.
IJOB0011	Error	Queue name is blank/reserved default, or concurrency is negative; queue attribute.	Use a non-reserved stable name and non-negative concurrency.
IJOB0012	Error	A valid job handler returns a value, such as ValueTask<T>, instead of ValueTask; handler method.	Return non-generic ValueTask; background jobs have no return-value consumer.
IJOB0013	Error	Payload graph cannot receive generated JSON metadata; offending request member/type.	Use supported concrete values, one-dimensional arrays, List<T> or Dictionary<TKey, TValue>.
IJOB0014	Error	Context graph cannot receive generated JSON metadata; offending context member/type.	Apply the same AOT-safe shape rules as a job payload.
IJOB0015	Warning	AddToBatchAsync(JobDetails, ..., ContinuationOptions.Detached); the Detached argument.	Use ScheduleAfter for detached work or a batch-joining option.

Related runtime failures

Some facts depend on runtime values or durable state and cannot be diagnosed at compile time:

• duplicate context extractor keys throw ImmediateJobException while capturing;
• negative delays, over-128-character group IDs and invalid dashboard intervals throw argument exceptions;
• invalid dynamic cron/time zones fail when adding/updating the schedule;
• graph operations on Redis or another queue-only provider throw NotSupportedException;
• fair acquisition on Redis throws NotSupportedException when UseFairQueues is enabled;
• single-server mode rejects providers without replica, recurring and graph capabilities and detects multiple-process replica drift;
• unknown stored job names fail terminally because no generated definition can execute them;
• unknown context slices are logged and skipped so rolling deployments can continue;
• retry/delete/cancel operations reject incompatible lifecycle states with ImmediateJobException (HTTP 409 in the dashboard).

If generation appears absent, first confirm the class is partial, carries both attributes, has a valid method signature, and that the project references Immediate.Jobs directly. Then inspect the IJ.*.g.cs files described in How it works.