diff --git a/chat.go b/chat.go
index 31d942e..eb1dcfa 100644
--- a/chat.go
+++ b/chat.go
@@ -14,14 +14,20 @@ import (
 	"github.com/revrost/go-openrouter"
 )
 
+type ToolReasoning struct {
+	Format    string `msgpack:"format"`
+	Encrypted string `msgpack:"encrypted"`
+}
+
 type ToolCall struct {
-	ID      string  `msgpack:"id"`
-	Name    string  `msgpack:"name"`
-	Args    string  `msgpack:"args"`
-	Result  string  `msgpack:"result,omitempty"`
-	Done    bool    `msgpack:"done,omitempty"`
-	Invalid bool    `msgpack:"invalid,omitempty"`
-	Cost    float64 `msgpack:"cost,omitempty"`
+	ID        string         `msgpack:"id"`
+	Name      string         `msgpack:"name"`
+	Args      string         `msgpack:"args"`
+	Result    string         `msgpack:"result,omitempty"`
+	Done      bool           `msgpack:"done,omitempty"`
+	Invalid   bool           `msgpack:"invalid,omitempty"`
+	Cost      float64        `msgpack:"cost,omitempty"`
+	Reasoning *ToolReasoning `msgpack:"reasoning,omitempty"`
 }
 
 type TextFile struct {
@@ -69,7 +75,7 @@ func (t *ToolCall) AsAssistantToolCall(content string) openrouter.ChatCompletion
 		content = " "
 	}
 
-	return openrouter.ChatCompletionMessage{
+	call := openrouter.ChatCompletionMessage{
 		Role: openrouter.ChatMessageRoleAssistant,
 		Content: openrouter.Content{
 			Text: content,
@@ -85,6 +91,20 @@ func (t *ToolCall) AsAssistantToolCall(content string) openrouter.ChatCompletion
 			},
 		},
 	}
+
+	if t.Reasoning != nil {
+		call.ReasoningDetails = []openrouter.ChatCompletionReasoningDetails{
+			{
+				Type:   openrouter.ReasoningDetailsTypeEncrypted,
+				Data:   t.Reasoning.Encrypted,
+				ID:     t.ID,
+				Format: t.Reasoning.Format,
+				Index:  0,
+			},
+		}
+	}
+
+	return call
 }
 
 func (t *ToolCall) AsToolMessage() openrouter.ChatCompletionMessage {
@@ -521,6 +541,19 @@ func RunCompletion(ctx context.Context, response *Stream, request *openrouter.Ch
 				tool.Name += call.Function.Name
 			}
 
+			if len(delta.ReasoningDetails) != 0 && tool.Reasoning == nil {
+				for _, details := range delta.ReasoningDetails {
+					if details.Type != openrouter.ReasoningDetailsTypeEncrypted {
+						continue
+					}
+
+					tool.Reasoning = &ToolReasoning{
+						Format:    details.Format,
+						Encrypted: details.Data,
+					}
+				}
+			}
+
 			open += strings.Count(call.Function.Arguments, "{")
 			close += strings.Count(call.Function.Arguments, "}")
 
diff --git a/go.mod b/go.mod
index f7e19e7..3e7829d 100644
--- a/go.mod
+++ b/go.mod
@@ -18,3 +18,5 @@ require (
 	golang.org/x/sys v0.37.0 // indirect
 	golang.org/x/term v0.36.0 // indirect
 )
+
+replace github.com/revrost/go-openrouter => github.com/coalaura/go-openrouter v0.0.2-0.20251118165837-080dd9683303
diff --git a/go.sum b/go.sum
index 08aa7a1..b758d9f 100644
--- a/go.sum
+++ b/go.sum
@@ -1,3 +1,5 @@
+github.com/coalaura/go-openrouter v0.0.2-0.20251118165837-080dd9683303 h1:Y7ROVL2NxI5Yc04fApAxqExkzBigrWiWv5ag209uNM0=
+github.com/coalaura/go-openrouter v0.0.2-0.20251118165837-080dd9683303/go.mod h1:jZFcumFqvS25o8oEQc1/+4yeK7lHDSnwPMIJ/pKPdNc=
 github.com/coalaura/plain v0.2.0 h1:naGiTT1nmZO78IGHOajm0wc/X4sqaG6g3CSR3Ha9f6w=
 github.com/coalaura/plain v0.2.0/go.mod h1:HR/sQt288EMTF3aSEGKHwPmGYFU4FOrfarMUf6ifnLo=
 github.com/containerd/console v1.0.5 h1:R0ymNeydRqH2DmakFNdmjR2k0t7UPuiOV/N/27/qqsc=
@@ -12,8 +14,6 @@ github.com/goccy/go-yaml v1.18.0 h1:8W7wMFS12Pcas7KU+VVkaiCng+kG8QiFeFwzFb+rwuw=
 github.com/goccy/go-yaml v1.18.0/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/revrost/go-openrouter v0.2.6 h1:5riNi1FaWHIC2A2EP5hGunUGfU998vcz+CsIWsOWjx0=
-github.com/revrost/go-openrouter v0.2.6/go.mod h1:jZFcumFqvS25o8oEQc1/+4yeK7lHDSnwPMIJ/pKPdNc=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/vmihailenco/msgpack/v5 v5.4.1 h1:cQriyiUvjTwOHg8QZaPihLWeRAAVoCpE00IUPn0Bjt8=