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Emit AG-UI events for hosted MCP tool calls and results #1121

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5f07ebd
Emit AG-UI events for hosted MCP tool calls and results
PratikDhanave Sep 20, 2026
e2f61a3
Address review: assert full MCP tool-call lifecycle in AG-UI test
PratikDhanave Sep 21, 2026
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21 changes: 11 additions & 10 deletions go.mod
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,8 +7,8 @@ require (
github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.14.1
github.com/a2aproject/a2a-go/v2 v2.5.0
github.com/ag-ui-protocol/ag-ui/sdks/community/go v0.0.0-20260312103001-8e7ab1df34c8
github.com/anthropics/anthropic-sdk-go v1.72.0
github.com/github/copilot-sdk/go v1.0.13
github.com/anthropics/anthropic-sdk-go v1.73.0
github.com/github/copilot-sdk/go v1.0.14
github.com/gofrs/flock v0.13.1
github.com/google/jsonschema-go v0.4.3
github.com/google/uuid v1.6.0
Expand All @@ -22,12 +22,12 @@ require (
go.opentelemetry.io/otel/trace v1.46.0
golang.org/x/sync v0.23.0
google.golang.org/genai v1.71.0
google.golang.org/grpc v1.83.2
google.golang.org/grpc v1.84.0
)

require (
cloud.google.com/go v0.116.0 // indirect
cloud.google.com/go/auth v0.18.2 // indirect
cloud.google.com/go/auth v0.20.0 // indirect
cloud.google.com/go/compute/metadata v0.9.0 // indirect
github.com/Azure/azure-sdk-for-go/sdk/internal v1.12.0 // indirect
github.com/AzureAD/microsoft-authentication-library-for-go v1.8.0 // indirect
Expand All @@ -36,14 +36,14 @@ require (
github.com/cespare/xxhash/v2 v2.3.0 // indirect
github.com/coder/websocket v1.8.15 // indirect
github.com/ebitengine/purego v0.10.1 // indirect
github.com/felixge/httpsnoop v1.0.4 // indirect
github.com/felixge/httpsnoop v1.1.0 // indirect
github.com/go-logr/logr v1.4.4 // indirect
github.com/go-logr/stdr v1.2.2 // indirect
github.com/golang-jwt/jwt/v5 v5.3.1 // indirect
github.com/google/go-cmp v0.7.0 // indirect
github.com/google/s2a-go v0.1.9 // indirect
github.com/googleapis/enterprise-certificate-proxy v0.3.11 // indirect
github.com/googleapis/gax-go/v2 v2.17.0 // indirect
github.com/googleapis/enterprise-certificate-proxy v0.3.15 // indirect
github.com/googleapis/gax-go/v2 v2.22.0 // indirect
github.com/gorilla/websocket v1.5.3 // indirect
github.com/invopop/jsonschema v0.14.0 // indirect
github.com/kylelemons/godebug v1.1.0 // indirect
Expand All @@ -59,7 +59,7 @@ require (
github.com/tidwall/sjson v1.2.5 // indirect
github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
go.opentelemetry.io/auto/sdk v1.2.1 // indirect
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.61.0 // indirect
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0 // indirect
go.yaml.in/yaml/v4 v4.0.0-rc.2 // indirect
golang.org/x/crypto v0.55.0 // indirect
golang.org/x/mod v0.38.0 // indirect
Expand All @@ -68,7 +68,8 @@ require (
golang.org/x/sys v0.47.0 // indirect
golang.org/x/text v0.41.0 // indirect
golang.org/x/time v0.15.0 // indirect
google.golang.org/genproto/googleapis/api v0.0.0-20260526163538-3dc84a4a5aaa // indirect
google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
google.golang.org/api v0.278.0 // indirect
google.golang.org/genproto/googleapis/api v0.0.0-20260706201446-f0a921348800 // indirect
google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 // indirect
google.golang.org/protobuf v1.36.11 // indirect
)
44 changes: 24 additions & 20 deletions go.sum
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
cloud.google.com/go v0.116.0 h1:B3fRrSDkLRt5qSHWe40ERJvhvnQwdZiHu0bJOpldweE=
cloud.google.com/go v0.116.0/go.mod h1:cEPSRWPzZEswwdr9BxE6ChEn01dWlTaF05LiC2Xs70U=
cloud.google.com/go/auth v0.18.2 h1:+Nbt5Ev0xEqxlNjd6c+yYUeosQ5TtEUaNcN/3FozlaM=
cloud.google.com/go/auth v0.18.2/go.mod h1:xD+oY7gcahcu7G2SG2DsBerfFxgPAJz17zz2joOFF3M=
cloud.google.com/go/auth v0.20.0 h1:kXTssoVb4azsVDoUiF8KvxAqrsQcQtB53DcSgta74CA=
cloud.google.com/go/auth v0.20.0/go.mod h1:942/yi/itH1SsmpyrbnTMDgGfdy2BUqIKyd0cyYLc5Q=
cloud.google.com/go/compute/metadata v0.9.0 h1:pDUj4QMoPejqq20dK0Pg2N4yG9zIkYGdBtwLoEkH9Zs=
cloud.google.com/go/compute/metadata v0.9.0/go.mod h1:E0bWwX5wTnLPedCKqk3pJmVgCBSM6qQI1yTBdEb3C10=
github.com/Azure/azure-sdk-for-go/sdk/azcore v1.23.1 h1:zvXfGJCWvywnCA814d8ZiVyt+fm9nnTE8xSb99zRyfo=
Expand All @@ -20,8 +20,8 @@ github.com/a2aproject/a2a-go/v2 v2.5.0 h1:ZdcFoxv+nZTUV0i2ue5hES76YCANFPG9vjqd7v
github.com/a2aproject/a2a-go/v2 v2.5.0/go.mod h1:NcRp/ZHxgMzDj12/BteIC2gOjljuEBKaGRfEdJ2lNSI=
github.com/ag-ui-protocol/ag-ui/sdks/community/go v0.0.0-20260312103001-8e7ab1df34c8 h1:gcgM2iVSJ+5v1Li2O2xBm8jdY9bIo0coZdOlXOd0uLU=
github.com/ag-ui-protocol/ag-ui/sdks/community/go v0.0.0-20260312103001-8e7ab1df34c8/go.mod h1:ERAMOexUee4AIuoxksuuGoEcHl3aqLwaazjGwlR9ZCI=
github.com/anthropics/anthropic-sdk-go v1.72.0 h1:T0qQWWfygiL24lqEQaffRXCvEeno3yiv/mFzUdY1E88=
github.com/anthropics/anthropic-sdk-go v1.72.0/go.mod h1:x+lPk/cCl48uRegeP0hlYYBN1b7bEBTveInIMgLicnY=
github.com/anthropics/anthropic-sdk-go v1.73.0 h1:brLt0oVV6LH0YcG6O6G3pBnIVDJQ/QPoXul+OJHXEFc=
github.com/anthropics/anthropic-sdk-go v1.73.0/go.mod h1:x+lPk/cCl48uRegeP0hlYYBN1b7bEBTveInIMgLicnY=
github.com/bahlo/generic-list-go v0.2.0 h1:5sz/EEAK+ls5wF+NeqDpk5+iNdMDXrh3z3nPnH1Wvgk=
github.com/bahlo/generic-list-go v0.2.0/go.mod h1:2KvAjgMlE5NNynlg/5iLrrCCZ2+5xWbdbCW3pNTGyYg=
github.com/buger/jsonparser v1.1.2 h1:frqHqw7otoVbk5M8LlE/L7HTnIq2v9RX6EJ48i9AxJk=
Expand All @@ -36,10 +36,10 @@ github.com/dnaeon/go-vcr v1.2.0 h1:zHCHvJYTMh1N7xnV7zf1m1GPBF9Ad0Jk/whtQ1663qI=
github.com/dnaeon/go-vcr v1.2.0/go.mod h1:R4UdLID7HZT3taECzJs4YgbbH6PIGXB6W/sc5OLb6RQ=
github.com/ebitengine/purego v0.10.1 h1:dewVBCBT2GaMu1SrNTYxQhgQBethzfhiwvZiLGP/qyY=
github.com/ebitengine/purego v0.10.1/go.mod h1:iIjxzd6CiRiOG0UyXP+V1+jWqUXVjPKLAI0mRfJZTmQ=
github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
github.com/github/copilot-sdk/go v1.0.13 h1:sc4kLSJksYb6lsUwFV48P4jDJ06PQR+4OzpqOhvxho0=
github.com/github/copilot-sdk/go v1.0.13/go.mod h1:U0STg9Jdv9LDwtkUtcUJCzPQ4KTnKakRfP+1LhEx248=
github.com/felixge/httpsnoop v1.1.0 h1:3YtUj32ZZkqZtt3sZZsClsymw/QDuVfpNhoA31zeORc=
github.com/felixge/httpsnoop v1.1.0/go.mod h1:Zqxgdd+1Rkcz8euOqdr7lqgCRJztwr5hp9vDSi5UZCE=
github.com/github/copilot-sdk/go v1.0.14 h1:DeHPF2CbxRCe4EeAjYIo7v3CovGEEMHsrURUNaogf5A=
github.com/github/copilot-sdk/go v1.0.14/go.mod h1:U0STg9Jdv9LDwtkUtcUJCzPQ4KTnKakRfP+1LhEx248=
github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
github.com/go-logr/logr v1.4.4 h1:tG4xh9yMsRCAiodLVTxyrkzSZ9+o0L1Kg/+cPVcbP/8=
github.com/go-logr/logr v1.4.4/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
Expand All @@ -59,10 +59,10 @@ github.com/google/s2a-go v0.1.9 h1:LGD7gtMgezd8a/Xak7mEWL0PjoTQFvpRudN895yqKW0=
github.com/google/s2a-go v0.1.9/go.mod h1:YA0Ei2ZQL3acow2O62kdp9UlnvMmU7kA6Eutn0dXayM=
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
github.com/googleapis/enterprise-certificate-proxy v0.3.11 h1:vAe81Msw+8tKUxi2Dqh/NZMz7475yUvmRIkXr4oN2ao=
github.com/googleapis/enterprise-certificate-proxy v0.3.11/go.mod h1:RFV7MUdlb7AgEq2v7FmMCfeSMCllAzWxFgRdusoGks8=
github.com/googleapis/gax-go/v2 v2.17.0 h1:RksgfBpxqff0EZkDWYuz9q/uWsTVz+kf43LsZ1J6SMc=
github.com/googleapis/gax-go/v2 v2.17.0/go.mod h1:mzaqghpQp4JDh3HvADwrat+6M3MOIDp5YKHhb9PAgDY=
github.com/googleapis/enterprise-certificate-proxy v0.3.15 h1:xolVQTEXusUcAA5UgtyRLjelpFFHWlPQ4XfWGc7MBas=
github.com/googleapis/enterprise-certificate-proxy v0.3.15/go.mod h1:vqVt9yG9480NtzREnTlmGSBmFrA+bzb0yl0TxoBQXOg=
github.com/googleapis/gax-go/v2 v2.22.0 h1:PjIWBpgGIVKGoCXuiCoP64altEJCj3/Ei+kSU5vlZD4=
github.com/googleapis/gax-go/v2 v2.22.0/go.mod h1:irWBbALSr0Sk3qlqb9SyJ1h68WjgeFuiOzI4Rqw5+aY=
github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
github.com/invopop/jsonschema v0.14.0 h1:MHQqLhvpNUZfw+hM3AZDYK7jxO8FZoQeQM77g8iyZjg=
Expand Down Expand Up @@ -107,8 +107,8 @@ github.com/yosida95/uritemplate/v3 v3.0.2 h1:Ed3Oyj9yrmi9087+NczuL5BwkIc4wvTb5zI
github.com/yosida95/uritemplate/v3 v3.0.2/go.mod h1:ILOh0sOhIJR3+L/8afwt/kE++YT040gmv5BQTMR2HP4=
go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.61.0 h1:F7Jx+6hwnZ41NSFTO5q4LYDtJRXBf2PD0rNBkeB/lus=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.61.0/go.mod h1:UHB22Z8QsdRDrnAtX4PntOl36ajSxcdUMt1sF7Y6E7Q=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0 h1:8tvICD4vSTOOsNrsI4Ljf6C+6UKvpTEH5XY3JMoyPoo=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0/go.mod h1:z9+yiacE0IHRqM4qFfkbt/JYlmYXgss8GY/jXoNuPJI=
go.opentelemetry.io/otel v1.46.0 h1:FHt5/CDyVxi/8IM1CH7VE/rRgq3kLHa2mSTVMO8AWyc=
go.opentelemetry.io/otel v1.46.0/go.mod h1:Gj3SEScelsNC45tp4nSxRYlS+f5iez7W8XPMCt905kE=
go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.46.0 h1:KdRxPiAoMptR3vfWzvjjvutTsSiwbC2uG0496rzZNfo=
Expand Down Expand Up @@ -151,14 +151,18 @@ golang.org/x/tools v0.48.0 h1:3+hClM1aLL5mjMKm5ovokw9epgRXPuu2tILgismM6RE=
golang.org/x/tools v0.48.0/go.mod h1:08xX0orndb/F7jJxGDicx061tyd5pcMto75YMAXr6lk=
gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
google.golang.org/api v0.278.0 h1:W7jiRvRi53VYFfZ/HoZjQBtJk7gOFbHD8ot1RzVZU6E=
google.golang.org/api v0.278.0/go.mod h1:B9TqLBwJqVjp1mtt7WeoQwWRwvu/400y5lETOql+giQ=
google.golang.org/genai v1.71.0 h1:Wfo9n0uSzMhZH7d+rP7QxxSWELEDSD4z6O8W/C9s3oM=
google.golang.org/genai v1.71.0/go.mod h1:mDdPDFXo1Ats7f1WXVyZgWb/CkMzFWTWJruIMy7hGIU=
google.golang.org/genproto/googleapis/api v0.0.0-20260526163538-3dc84a4a5aaa h1:Kjn0N0tCrDgiAFW+lGO4JZ3ck44CehvJQMAwj9QF0G8=
google.golang.org/genproto/googleapis/api v0.0.0-20260526163538-3dc84a4a5aaa/go.mod h1:q4lMZS6kskjT5HvCPrnnypcDPVJqT/f4nfxmkE7gryY=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa h1:mZHHdPZl0dbGHCflZgAq/Q468DWVFcU2whhB2KAo8fk=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
google.golang.org/grpc v1.83.2 h1:EManeRomTObA0BU7I8vXgg/78uE5MJ9M8B39EX2WscU=
google.golang.org/grpc v1.83.2/go.mod h1:YPI1hK3kDked6iHvgX3tR0y+nX/qpMFKhPgFsokw1S8=
google.golang.org/genproto v0.0.0-20260319201613-d00831a3d3e7 h1:XzmzkmB14QhVhgnawEVsOn6OFsnpyxNPRY9QV01dNB0=
google.golang.org/genproto v0.0.0-20260319201613-d00831a3d3e7/go.mod h1:L43LFes82YgSonw6iTXTxXUX1OlULt4AQtkik4ULL/I=
google.golang.org/genproto/googleapis/api v0.0.0-20260706201446-f0a921348800 h1:admdQBe8jR3VWhBsUrAOaF2Qw6K/+p5pSm1GN8+6Fw4=
google.golang.org/genproto/googleapis/api v0.0.0-20260706201446-f0a921348800/go.mod h1:FPk7EXUKMtImne7AmknoYjT4QXqKIzzRbeQIXzLk6fQ=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800 h1:qEHAMpSaUhtD0p3NbEEI83HwNGFxEwaSJ1G9PLnCBZE=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260706201446-f0a921348800/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
google.golang.org/grpc v1.84.0 h1:soMyaPJ8pAak5PIQ0DGBUir0XRo2fRoMqhNWMLlLxO0=
google.golang.org/grpc v1.84.0/go.mod h1:ljCht0DrxQrXBDRTZp52Qxh3Ffk8CdYm2sj4O2QN2C0=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
Expand Down
27 changes: 27 additions & 0 deletions provider/aguiprovider/hosting_events.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -314,6 +314,33 @@ func contentToEvents(content message.Content, messageID string) ([]aguiEvents.Ev
// message ID. MEAI batches all results under a shared MessageId, which
// collapses them in FE reconciliation when the same id is reused.
return []aguiEvents.Event{aguiEvents.NewToolCallResultEvent("result-"+callID, callID, contentStr)}, nil
case *message.MCPServerToolCallContent:
// A hosted MCP tool call the server ran; surface it as an AG-UI tool
// call (start/args/end) rather than dropping it, matching the Python
// host's _emit_mcp_tool_call.
callID := c.CallID
if callID == "" {
callID = aguiEvents.GenerateToolCallID()
}
args := strings.TrimSpace(c.Arguments)
if args == "" {
args = "{}"
}
return []aguiEvents.Event{
aguiEvents.NewToolCallStartEvent(callID, c.Name),

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MCP tool-call events lose the parentMessageId association that the sibling FunctionCallContent case sets a few lines above (WithParentMessageID(messageID), with the comment "Associate the tool call with its assistant message ... Matches the Python host").

Upstream, both _emit_tool_call (regular function calls) and _emit_mcp_tool_call — the function this PR's own description cites as the Python source — call _track_tool_call_segment(flow, tool_call_id) and pass the result as parent_message_id to ToolCallStartEvent (python/packages/ag-ui/agent_framework_ag_ui/_run_common.py, _emit_mcp_tool_call ~L1002-1008, _track_tool_call_segment ~L574). Python does not special-case MCP calls to omit it.

Because toAgentMessages (hosting_convert.go) coalesces consecutive assistant messages by keying off ToolCallStartEvent.parentMessageId (see agui.go's pendingToolCall{MessageID: cmp.Or(deref(e.ParentMessageID), e.ToolCallID)}), an MCP tool call streamed without parentMessageId won't coalesce with the surrounding assistant message the way a regular function call does — risking the same "two consecutive single-tool-call assistant messages without intervening tool results" HTTP 400 the FunctionCallContent fix was meant to prevent, now specifically for hosted MCP tool calls.

Suggested fix: pass WithParentMessageID(messageID) (guarded on messageID != "") to NewToolCallStartEvent here too, matching the FunctionCallContent case and the Python _emit_mcp_tool_call/_track_tool_call_segment behavior.

aguiEvents.NewToolCallArgsEvent(callID, args),
aguiEvents.NewToolCallEndEvent(callID),
}, nil
case *message.MCPServerToolResultContent:
callID := c.CallID
if callID == "" {
callID = aguiEvents.GenerateToolCallID()
}
contentStr, err := serializeToolResult(c.Outputs)
if err != nil {
return nil, err
}
return []aguiEvents.Event{aguiEvents.NewToolCallResultEvent("result-"+callID, callID, contentStr)}, nil
case *message.URIContent:
// AG-UI has no native reference/attachment event; surface the URI as
// text so it is not silently dropped (mirrors the DataContent fallback
Expand Down
32 changes: 32 additions & 0 deletions provider/aguiprovider/hosting_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -201,6 +201,38 @@ func TestHandler_StateSnapshotEmitsStateEvent(t *testing.T) {
}
}

// Hosted MCP tool calls/results must be surfaced as AG-UI tool-call events
// rather than dropped, matching the Python host.
func TestHandler_MCPToolCallAndResultEmitEvents(t *testing.T) {
a := newTestAgent(func(_ context.Context, _ []*message.Message, _ ...agent.Option) iter.Seq2[*agent.ResponseUpdate, error] {
return func(yield func(*agent.ResponseUpdate, error) bool) {
yield(&agent.ResponseUpdate{
MessageID: "msg-1",
Role: message.RoleAssistant,
Contents: message.Contents{
&message.MCPServerToolCallContent{CallID: "m1", Name: "mcp_tool", ServerName: "github", Arguments: `{}`},
&message.MCPServerToolResultContent{CallID: "m1", Outputs: message.Contents{&message.TextContent{Text: "ok"}}},
},
}, nil)
}
})
h := aguiprovider.NewJSONHTTPHandler(a, aguiprovider.HandlerConfig{})

body := `{"threadId":"thread-1","runId":"run-1","messages":[{"id":"u1","role":"user","content":"ping"}]}`
req := httptest.NewRequest(http.MethodPost, "/", strings.NewReader(body))
rr := httptest.NewRecorder()
h.ServeHTTP(rr, req)

content := rr.Body.String()
// Assert the full tool-call lifecycle and the serialized result, so a
// regression dropping any event or the payload is caught.
for _, want := range []string{"TOOL_CALL_START", "mcp_tool", "TOOL_CALL_ARGS", "TOOL_CALL_END", "TOOL_CALL_RESULT", "ok"} {
if !strings.Contains(content, want) {
t.Fatalf("expected MCP tool-call SSE stream to contain %q, got %q", want, content)
}
}
}

func TestHandler_MixedToolInvocations_SuppressesServerToolResults(t *testing.T) {
a := newTestAgent(func(_ context.Context, _ []*message.Message, _ ...agent.Option) iter.Seq2[*agent.ResponseUpdate, error] {
return func(yield func(*agent.ResponseUpdate, error) bool) {
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