White paper: Choosing between the GitHub Copilot and Standard harnesses in Copilot Studio
The Standard harness and GitHub Copilot harness are two authoring and runtime options within Microsoft Copilot Studio. A harness is the operating layer between the model and the agent’s configuration. It determines how the model receives context, uses instructions and tools, interprets results, and moves through a task toward completion. Put simply, the model provides the reasoning capability, while the harness equips and directs it. Both harnesses are built for task-based, multi-step agents that create real business value, but they are suited to different scenarios. The Standard harness supports consistent, reliable execution of bounded business processes, while the GitHub Copilot harness extends these capabilities to longer-running, coordination-heavy, and reasoning-intensive work at a larger scale. This paper explains the key differences, tradeoffs, and scenarios to help you choose which harness is right for your business process. Read the full paper by clicking the PDF attachment below.Unanswered Questions on GitHub Copilot Harness in Copilot Studio
We're piloting the GitHub Copilot harness in Copilot Studio (GA August 2026) and several operational and architectural details remain undocumented in the GA FAQ, Microsoft Learn, or licensing guides. Looking for official answers or PM contacts on: Architecture & Execution – When the harness breaks tasks into subtasks, does it use internal sub-agents or only skills/connected agents, what are the exact timeout/retry/max-execution-duration limits for long-running workflows, and are planning/context-retrieval/orchestration internals documented anywhere or is the orchestrator a black box? Model Selection – Can individual skills within one agent use different models or is selection strictly agent-level, how are models chosen internally when multiple skills execute, are any internal models developer-configurable, and what's the roadmap for models being added/retired/deprecated plus the lag between public release and Copilot Studio availability? Cost & Token Optimization – How exactly is the ~45% token reduction achieved, how much control do makers have over context/caching/retrieval/tool calls, what are per-model credit consumption characteristics, which models are most cost-effective for specific workloads, and what's the minimum credit cost for trivial interactions? Memory Management – What are retention periods for session/working/agent memory beyond the documented 28-day user-memory expiry, is true long-term memory supported, and what changed versus earlier implementations? Knowledge Retrieval – Can skills or system instructions influence retrieval strategy/document selection/prioritization/filtering, can planning stages perform conflict/duplicate/version detection before retrieval, and how does the harness decide which sources to search? Apps Feature – What is the "Apps (preview)" capability for, when does it GA, and how does it differ from workflows/skills/adaptive cards/agents? Billing & Credit Sizing – Is there a framework to classify users/agents by expected consumption and size credit allocation per group (citizen vs pro developers), and what's the minimum/typical consumption for simple/medium/heavy interactions? Governance & Admin – Can usage limits be set at user level (not just environment/agent), is there an API/IaC path for large-scale credit assignment, can non-admins view their own consumption/remaining allocation, and is there a self-service request-more-credits dashboard? ALM & Environments – What's the recommended path to move harness agents across Dev/Test/UAT/Prod (Solutions/ALM "setup differs" per parity chart—how?), does GitHub integration replace or complement solution-based deployment, are there recommended AgentOps practices for source control/releases/versioning, and what baseline credits and onboarding model are suggested for citizen developers under usage billing—any enterprise reference implementations?Update: Root Cause Identified
Hi everyone, I would like to share the root cause and solution in case someone else encounters the same issue. The Problem I created several agent flows directly in Power Automate using: https://make.powerautomate.com The flows were configured correctly: The flow starts with When an agent calls the flow The flow ends with Respond to the agent The flow and agent are in the same environment The flow is included in a solution The flow is published and fully functional The flows could be added to an agent and executed successfully. However, unlike flows created directly from Copilot Studio, they did not appear in the Global Tools directory. What I Investigated I verified: Trigger configuration Respond to the agent action Environment consistency Solution membership Publish all customizations Asynchronous response settings Synchronization delays between Power Automate and Copilot Studio None of these were the root cause. Root Cause The issue was related to the workflow Plan. I discovered that: Flows created directly in Power Automate were assigned: Plan = The user running the flow Flows created directly in Copilot Studio were assigned: Plan = Copilot Studio Although the Power Automate flow was fully functional and could be used by the agent, it was not visible in the Global Tools directory. Solution After changing the workflow Plan to: Plan = Copilot Studio the flow immediately appeared in the Global Tools directory. Configuration Location The setting can be found in the workflow properties under: Primary owner → Plan Important Note Based on my testing, changing the Plan to Copilot Studio appears to be a one-way operation and may not be reversible. It may be a good idea to export or save the flow before making the change. Acknowledgements Special thanks to sohnash for reproducing the scenario and providing troubleshooting suggestions, and to Patty_Velasquez for sharing similar observations that helped confirm the behavior. Hopefully this helps others who encounter the same issue. Best regards, Adhonaï KOUKAPower Automate Flows Created Outside Copilot Studio Not Appearing in Tools
Hello everyone, I'm facing an issue with Copilot Studio and would appreciate your advice. Context I have several Power Automate flows that I created directly from: https://make.powerautomate.com My goal is to use these flows as tools within a Copilot Studio agent. All components are in the same Power Platform environment. What I've verified The flows use the "When an agent calls a flow" trigger. The flows end with "Respond to the agent". The flows are saved and published. The agent and flows are added to the same Solution. The solution has been published. I am using the same account and environment for both Power Automate and Copilot Studio. The Issue Flows that are created directly from Copilot Studio appear correctly under: Tools → Add Tool However, flows created from Power Automate (make.powerautomate.com) do not appear in the Tools list, even though they have the same trigger and response configuration. Question Are there additional requirements for a Power Automate flow to be discoverable by Copilot Studio? For example: Does the flow need to be an Agent Flow rather than a standard Cloud Flow? Are there known synchronization or caching issues between Power Automate and Copilot Studio? Is there a specific setting, solution configuration, or publishing step that I may have missed? Any guidance or experience with a similar issue would be greatly appreciated. Thank you!Free Copilot Credits for MCTs/ MVPs ?
Hello All The new Copilot Studio experience, powered by the GitHub Copilot harness, requires Copilot Credits for building, testing, and evaluating agents. In contrast, classic Copilot Studio requires Copilot Credits only after publishing. Is there a way for MCTs or MVPs to get Free access to Copilot Credits so they can test agents in the new Copilot Studio experience?Copilot Studio: “Get file content using path” fails for table-heavy DOCX files
Hi everyone, I'm investigating an issue with a Copilot Studio Standard Harness agent and would like to know whether others have encountered similar behavior. Scenario I have configured a tool in my agent using: Get file content using path The document is stored in my own OneDrive/SharePoint location and I have full access to it. This is not a chat file upload scenario and not a knowledge source indexing scenario. The agent is retrieving the document through a configured tool action. Behavior Observed Case 1 - Works The Word document contains approximately: ~4.1K words ~20 tables The agent successfully: Finds the file Retrieves the file Reads the content Generates a summary Case 2 - Fails I increase the document slightly: ~4.2K words More tables added The agent now returns a message similar to: The file was retrieved, but its content could not be converted to text. The response still indicates that: File found File retrieved Text extraction/conversion failed Important Observation Initially I thought this might be a word-count limitation, but additional testing suggests otherwise. I tested another document containing: More than 4.3K words Very few or no tables The agent processed that file successfully and generated a correct summary. Because of this, the issue appears to be related more to table-heavy DOCX content than to the total number of words. What Has Been Ruled Out The following do not appear to be the cause: File path issues Permissions/access issues File not found issues Connector authentication issues Large file size issues Chat file upload limitations Knowledge source indexing limitations The same tool and same retrieval approach continue working until the document becomes more table-heavy. Questions Has anyone experienced similar behavior with Get file content using path in Copilot Studio? Does Copilot Studio Standard Harness perform an internal DOCX-to-text conversion step after retrieving the file? Are there known limitations around processing Word documents that contain a large number of tables? Has anyone identified practical thresholds around table count, table complexity, or table-heavy technical documents? Is there a recommended workaround besides splitting the document into smaller files? Any insights, similar experiences, or Microsoft guidance would be greatly appreciated. Thanks!
All Copilot Studio Workflow Tools Suddenly Returning HTTP 403 Before Execution
Hello Copilot Studio Community, I am experiencing an authorization issue with multiple workflows connected to an agent built using the Copilot Studio new experience and new Workflows experience. These workflows worked successfully for multiple users yesterday. Today, all workflow tools connected to the agent began returning an immediate HTTP 403 authorization error. I did not intentionally change the agent, workflows, environment, or workflow permissions before the issue started. Error message: You don’t have permission to use this tool. You’re signed in, but access to this resource is blocked. Error details: Authorization - 403 Example error information: Status: Failed Error message: Flow returned HTTP 403 Error code: Http403 Inner error code: NotSpecified Tool duration: Approximately 93 milliseconds Configuration: - Copilot Studio new agent experience - Copilot Studio new Workflows experience - Agent and workflows are in the same Power Platform environment - Workflows use the "When an agent calls the workflow" trigger - Each workflow includes a "Respond to the agent" action - Workflows are saved and published - Agent is saved and published Observed behavior: The problem affects several independent workflows, including: - New-request submission - Current-user identity resolution - Approval decisions - Requester justification - Executive decisions - Fulfillment updates For every affected workflow: - The agent fills the workflow inputs correctly. - The tool call fails almost immediately. - No corresponding run appears in the workflow Activity history. - The workflow trigger is never reached. - No workflow actions execute. Because no workflow run is created, the rejection appears to occur before workflow execution, possibly within the Copilot Studio agent-to-workflow authorization or invocation layer. Troubleshooting already completed: - Confirmed that all workflows are published. - Confirmed that the agent is published. - Tested in a completely new conversation. - Removed an affected workflow tool from the agent. - Saved the agent. - Added the same published workflow back to the agent. - Reconfigured and verified the tool inputs. - Republished the agent. - Confirmed that no workflow Activity run is created. - Confirmed that the issue affects multiple workflows rather than one specific workflow. Removing and re-adding the workflow did not resolve the problem. Questions for the community: 1. Is anyone else currently experiencing HTTP 403 errors when Copilot Studio agents invoke workflows? 2. Is this a known issue or regression in the new Workflows experience? 3. Is there an environment-level or tenant-level permission that controls agent-to-workflow invocation? 4. Could a tenant policy, Conditional Access change, service principal, connection reference, or workflow-sharing configuration cause all workflow tools to fail simultaneously? 5. Where can an administrator find detailed authorization logs when the workflow never creates a run? 6. Has anyone found a workaround for this issue? Any guidance or confirmation from others experiencing the same behavior would be appreciated. I can provide screenshots, complete error details, timestamps, and additional configuration information if needed. Thank you.
Microsoft AI Agent Creator Associate Certificate
Hello everyone, I have a question about the Microsoft AI Agent Creator Associate certification. I’m passionate about artificial intelligence and Microsoft Copilot Studio. I’m currently taking the training course and working toward earning the Microsoft AI Agent Creator Associate certification. My question is: Will earning this certification improve my chances of getting a job at Microsoft? If anyone in this community has earned this certification or has experience with it, I’d really appreciate your feedback. Has it helped you get hired by Microsoft or one of its partners? Thank you in advance for your advice and insights!
