fix(muster): call workflow tools through the call_tool meta-tool#1743
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The muster aggregator only exposes its meta-tools (list_tools, call_tool, ...) over MCP; concrete tools like core_workflow_list are not directly callable, so every workflow endpoint failed with "tool 'core_workflow_list' not found: tool not found" against real muster servers. Invoke the workflow tools through the call_tool meta-tool and unwrap its result envelope (with a fallback for servers that expose tools directly). Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: Cursor <cursoragent@cursor.com>
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Summary
/musterWorkflows page failed against real muster servers withtool 'core_workflow_list' not found: tool not found: the muster aggregator only exposes its meta-tools (list_tools,call_tool, ...) over MCP, so the fourcore_workflow_*tools are not directly callable.call_toolmeta-tool and unwraps its result envelope (the target tool's MCP result serialized as JSON inside the meta-tool's text content block), with a fallback for servers that expose tools directly.Verified against
muster.gazelle.awsprod.gigantic.io/mcp:tools/listreturns only the 11 meta-tools, directtools/call core_workflow_listreturns-32602 tool not found, andcall_toolwith{name: "core_workflow_list"}returns the workflow list. The same meta-tools-only surface applies to local muster instances.Follow-up to #1735/#1738/#1740 — with per-user auth working and the SSE interop hang fixed, this was the remaining blocker for the Workflows page.
Test plan
backstage-cli package testin plugins/muster-backend (28 tests, incl. new envelope/meta-tool cases)backstage-cli package lintMade with Cursor