Connected BIM Data Wins: Revit .NET 10, Forma and openBIM
Original English video · 24 September 2026. The article includes a dated correction of Content Catalog API status.
Edition: 24 September 2026 · Category: BIM News
This is an archived English edition. The briefing below preserves the original episode’s reporting and analysis, with paragraph headings added for reading. Words such as “today”, “planned” and “upcoming” refer to the edition date, not the website publication date. Product status, prices and deadlines should be checked again before a new decision.
The edition’s main signal: on September 21, the production Autodesk Platform Services Revit Automation engine moved to Revit 2026.5 and dot NET 10. This is not an ordinary desktop update. AppBundle jobs running unattended in the cloud now execute in a new environment. The advance-warning stage is over, so organisations should move to post-upgrade regression testing and output comparison. Compatibility is now demonstrated by rerunning a known input and comparing it with an approved reference result, not by assuming that a successful status proves equivalence.
Production engine migration
The production Revit Automation engine has moved to Revit 2026.5 and dot NET 10. Autodesk announced in advance that the Revit 2026 Automation engine would be upgraded on September 21. Most existing AppBundles are expected to continue working, but Autodesk recommended checking Revit API behaviour, third-party libraries and the complete automated workflow. The action is not to stop at a successful job status. Rerun reference jobs and compare RVT, IFC and PDF outputs, quantities, warnings, logs and execution time.
Fallback and continuity
No old engine fallback is planned for security reasons. Autodesk does not plan to keep the Revit 2026 Automation engine on an earlier Revit or dot NET version. Rollback therefore cannot mean returning to an old Autodesk cloud runtime. The organisation needs its own fallback: stop publication, retain the last approved output, use a compatible local test or temporarily execute the process manually. Every production activity should have an owner, dependency versions, a reference output, a failure threshold and a continuity procedure.
Content Catalog API: corrected GA status
Archive correction, checked 25 October 2026: the original briefing reused the August public-beta status. Autodesk announced Content Catalog API general availability effective 14 September, before this edition. The upload workflow introduced in v2.1.0 forms part of the expanded API. The retired hub-discovery endpoint still requires migration; general availability does not remove integration testing or human approval. Use a quarantine collection, mandatory metadata, file checks and one controlled publisher identity. Source: https://aps.autodesk.com/blog/content-catalog-api-now-generally-available
Delegation and approval auditing
The Forma Reviews API has added stronger delegation and approval auditing. An approver can be allowed to modify the approver candidate list, while completed reviews return approved-by and approved-at data. Results can be filtered by final approver and date. Delegation prevents a workflow from stalling, but it changes the accountability chain. The person originally assigned and the person who finally approved are not necessarily the same. The audit record should preserve the initial approver, delegation event, delegating person, reason, final approver, timestamp and exact file issue.
Project metadata and large lists
File metadata definitions are available at project level, and lists can contain up to two thousand values. The Files API added a project-level custom-attribute definition query and a large-list type. Large lists use pagination. The public API can currently read them, but creation and editing remain in the user interface. These methods do not support BIM 360 projects. Discipline, system, classification and document-status dictionaries can be read centrally, but an integration that does not recognise the new type may silently omit values. Update type handling, implement pagination, log unknown types and distinguish Forma projects from legacy BIM 360 projects.
Data Exchange in coordination
Data Exchange now participates in Model Coordination, but not every version behaves in the same way. Data Exchange containers can be aggregated with other formats, inspected in the object table, coloured and transformed. New Exchanges created from Revit and Inventor can participate in automated clash detection. Full functionality requires the Exchange to have been created or updated after August 13 with the latest connectors. An older Exchange may be visible but lack Object Table, Save to Files or clash-detection support. Data Exchange is also not a file. It is a data container linked to its source. The coordination protocol should record the source model, connector version, creation date, included object set and last-update status.
Viewer Scene API migration
The new Scene API changes the contract for custom 3D content in APS Viewer. The documented, typed API manages geometry, materials, transforms and visibility for both loaded models and runtime-created content. Overlays and Scene Builder remain in Viewer 7, but Autodesk plans to deprecate them in Viewer 8. Developers of digital twins, sensors, trajectories, analytical results and XR annotations finally have a documented contract, but they must plan migration away from internal or legacy APIs. Inventory dependencies on viewer overlays, viewer impl and Scene Builder, then add visual regression tests and verify object identifiers and transforms.
AI-assisted legacy CAD migration
AI can accelerate the migration of legacy CAD automation, but an executable test remains the proof. Autodesk published a Claude Code skill example that rewrites an old AutoLISP and DCL process into a typed dot NET plug-in, unit and integration tests, and an APS Automation package. Five migrations were executed against the live cloud service. Seven representative files completed the full migration, and a dry run across sixty-two files produced an analysis. This demonstration is not a universal guarantee for decades of LISP libraries, especially those using COM, dialogs or undocumented behaviour. Accept an AI-generated migration only after source inventory, difference analysis, accoreconsole tests, a real WorkItem and a semantic comparison of the resulting DWG.
Analysis and practical implications
Today’s analysis. Cloud BIM automation is a versioned software supply chain.
The recommended chain is source model, AppBundle and dependencies, cloud engine version, WorkItem, output artefacts, deterministic quality assurance, approval and publication.
The greatest opportunity is to standardise repetitive Revit, AutoCAD, content-library, document-review and model-coordination processes so they become repeatable, auditable and independent of one user’s workstation.
The practical consequence is that every automation should be governed like a production software service. It needs a version register, a reproducible test set, operational monitoring, a named failure owner and a gate that prevents an invalid result from entering the common data environment. This control must cover more than source code. It must also cover the model version, content catalogue, metadata dictionary, review state and coordination container.
The opportunity for a BIM manager is to replace fragile person-dependent routines with controlled services and measurable quality gates. The shared lesson is that automation quality must be demonstrated at the information-delivery boundary, not only inside the script.
The main risks are these. A Success status is mistaken for a correct engineering result. The cloud engine changes without comparison against reference results. A third-party library compiles but behaves differently. Content is uploaded to the catalogue without quarantine and approval. Delegated approval loses its accountability history. A new metadata type is silently ignored. An old Data Exchange is visible but does not participate in clash detection. A Viewer scene looks correct while object identifiers or transforms have changed. AI-rewritten code loses exceptions embedded in the legacy automation.
Recommended plan.
Implementation step 1
create a register of all APS Automation activities, including engine, AppBundle, owner and production purpose.
Implementation step 2
maintain a small reference model and a known-correct output for every activity.
Implementation step 3
rerun the reference WorkItems after the Revit 2026.5 and dot NET 10 upgrade.
Implementation step 4
compare more than file sizes: element counts, parameters, IFC identifiers, quantities, sheets, PDF images and warnings.
Implementation step 5
record the engine, plug-in, dependency and input versions together with execution time.
Implementation step 6
stop publication automatically after a failed check and retain the previous approved output.
Implementation step 7
send Content Catalog uploads to a quarantine collection before the production library.
Implementation step 8
include review delegation and metadata changes in the audit report.
Implementation step 9
test Data Exchange and Scene API workflows with known coordinates and object identifiers.
Implementation step 10
evaluate AI migrations by real output equivalence rather than the amount of generated code.
For teaching, use a laboratory exercise in which students run the same Revit automation locally and in the cloud, compare the results, document dependencies and explain why a job that finishes without an error does not necessarily produce a correct result.
Today’s final signal: BIM automation reliability is not determined by code alone. It is a version chain covering the engine, dependencies, input, output, metadata and approval, and the chain must be retested after every platform change.
Original edition sources
These direct links were cited in the original scheduled brief. The scheduled message was retrieved in full on 25 October 2026; this recovery is not a claim of a fresh product test or new source validation.
- https://aps.autodesk.com/blog/revit-automation-engine-upgrading-revit-20265-and-net-10-september-21-2026 - https://aps.autodesk.com/blog/content-catalog-api-v210-upload-content-programmaticallypublic-beta - https://aps.autodesk.com/blog/forma-reviews-api-adds-approver-delegation-more-initiator-controls-and-approval-tracking - https://aps.autodesk.com/blog/files-api-now-supports-project-level-custom-attribute-definitions-and-large-drop-down-lists - https://aps.autodesk.com/blog/data-exchange-model-coordination - https://aps.autodesk.com/blog/introducing-scene-api-aps-viewer - https://aps.autodesk.com/blog/one-skill-one-lisp-one-automation-migrating-1998-autolisp-dialog-aps-automation
Watch the original edition
https://www.youtube.com/watch?v=uFkWntIcc-M
The original dated thumbnail is retained where available. Original per-topic artwork was not recovered for this legacy edition; no replacement artwork is represented as an original.
Archive media note: The original date-matched thumbnail and thematic artwork have not been recovered. No substitute is presented as original media.
