diff --git a/examples/acp-agent/tests/snapshots/fs-policy-reject/session.jsonl b/examples/acp-agent/tests/snapshots/fs-policy-reject/session.jsonl
index 9da7fd74cd..2e58233309 100644
--- a/examples/acp-agent/tests/snapshots/fs-policy-reject/session.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-policy-reject/session.jsonl
@@ -180,7 +180,7 @@
 {"type":"assistant/chunk","seq":178,"time":1783279386389,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" use"}}}
 {"type":"assistant/chunk","seq":179,"time":1783279386416,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" bash"}}}
 {"type":"assistant/chunk","seq":180,"time":1783279386416,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" with"}}}
-{"type":"assistant/chunk","seq":181,"time":1783279386416,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" sed"}}}
+{"type":"assistant/chunk","seq":181,"time":1783279386416,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" perl"}}}
 {"type":"assistant/chunk","seq":182,"time":1783279386416,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" to"}}}
 {"type":"assistant/chunk","seq":183,"time":1783279386444,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" replace"}}}
 {"type":"assistant/chunk","seq":184,"time":1783279386444,"data":{"turn":1,"step":2,"chunk":{"type":"reasoning-delta","index":0,"text":" \""}}}
@@ -203,9 +203,9 @@
 {"type":"assistant/chunk","seq":201,"time":1783279386643,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"\""}}}
 {"type":"assistant/chunk","seq":202,"time":1783279386643,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":": "}}}
 {"type":"assistant/chunk","seq":203,"time":1783279386643,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"\""}}}
-{"type":"assistant/chunk","seq":204,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"sed"}}}
-{"type":"assistant/chunk","seq":205,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":" -"}}}
-{"type":"assistant/chunk","seq":206,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"i"}}}
+{"type":"assistant/chunk","seq":204,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"perl"}}}
+{"type":"assistant/chunk","seq":205,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":" -0p"}}}
+{"type":"assistant/chunk","seq":206,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"i -e"}}}
 {"type":"assistant/chunk","seq":207,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":" '"}}}
 {"type":"assistant/chunk","seq":208,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"s"}}}
 {"type":"assistant/chunk","seq":209,"time":1783279386671,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"/"}}}
@@ -232,13 +232,13 @@
 {"type":"assistant/chunk","seq":230,"time":1783279386809,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":".txt"}}}
 {"type":"assistant/chunk","seq":231,"time":1783279386837,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"\""}}}
 {"type":"assistant/chunk","seq":232,"time":1783279386838,"data":{"turn":1,"step":2,"chunk":{"type":"tool-call-delta","index":1,"id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","argumentsDelta":"}"}}}
-{"type":"assistant/chunk","seq":233,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"reasoning","text":"The edit tool requires reading the file first due to the default fs-policy. However, the user explicitly instructed me NOT to use the read tool. I need to follow the user's instructions. The edit tool returned an error saying it requires reading the file first. I cannot comply with the user's request to not read the file because the tool enforces it. Let me try a different approach - maybe I can use subagent to do this, or use bash to do the replacement. Let me use bash with sed to replace \"blue\" with \"green\" without reading the file."}}}}
-{"type":"assistant/chunk","seq":234,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":1,"block":{"type":"tool-call","id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"sed -i 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}}}}
+{"type":"assistant/chunk","seq":233,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"reasoning","text":"The edit tool requires reading the file first due to the default fs-policy. However, the user explicitly instructed me NOT to use the read tool. I need to follow the user's instructions. The edit tool returned an error saying it requires reading the file first. I cannot comply with the user's request to not read the file because the tool enforces it. Let me try a different approach - maybe I can use subagent to do this, or use bash to do the replacement. Let me use bash with perl to replace \"blue\" with \"green\" without reading the file."}}}}
+{"type":"assistant/chunk","seq":234,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":1,"block":{"type":"tool-call","id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"perl -0pi -e 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}}}}
 {"type":"assistant/chunk","seq":235,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":227,"outputTokens":195,"cacheReadTokens":2048,"reasoningTokens":118}}}}
 {"type":"assistant/chunk","seq":236,"time":1783279386896,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":237,"time":1783279386897,"data":{"turn":1,"step":2,"content":[{"type":"reasoning","text":"The edit tool requires reading the file first due to the default fs-policy. However, the user explicitly instructed me NOT to use the read tool. I need to follow the user's instructions. The edit tool returned an error saying it requires reading the file first. I cannot comply with the user's request to not read the file because the tool enforces it. Let me try a different approach - maybe I can use subagent to do this, or use bash to do the replacement. Let me use bash with sed to replace \"blue\" with \"green\" without reading the file."},{"type":"tool-call","id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"sed -i 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}],"usage":{"inputTokens":227,"outputTokens":195,"cacheReadTokens":2048,"reasoningTokens":118}},"sourceEventSeqs":[77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236],"surfaceOp":"append"}
-{"type":"tool/call","seq":238,"time":1783279386897,"data":{"turn":1,"step":2,"callId":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"sed -i 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}}
-{"type":"tool/result","seq":239,"time":1783279386915,"data":{"turn":1,"step":2,"callId":"call_00_SvvpTh6bWybYXoO77NHg8535","content":[{"type":"text","text":"[stderr]\nsed: 1: \"settings.txt\n\": unterminated substitute pattern\n[exit code: 1]"}],"isError":false},"sourceEventSeqs":[238],"surfaceOp":"append"}
+{"type":"assistant/message","seq":237,"time":1783279386897,"data":{"turn":1,"step":2,"content":[{"type":"reasoning","text":"The edit tool requires reading the file first due to the default fs-policy. However, the user explicitly instructed me NOT to use the read tool. I need to follow the user's instructions. The edit tool returned an error saying it requires reading the file first. I cannot comply with the user's request to not read the file because the tool enforces it. Let me try a different approach - maybe I can use subagent to do this, or use bash to do the replacement. Let me use bash with perl to replace \"blue\" with \"green\" without reading the file."},{"type":"tool-call","id":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"perl -0pi -e 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}],"usage":{"inputTokens":227,"outputTokens":195,"cacheReadTokens":2048,"reasoningTokens":118}},"sourceEventSeqs":[77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236],"surfaceOp":"append"}
+{"type":"tool/call","seq":238,"time":1783279386897,"data":{"turn":1,"step":2,"callId":"call_00_SvvpTh6bWybYXoO77NHg8535","name":"bash","arguments":"{\"command\": \"perl -0pi -e 's/blue/green/g' settings.txt\", \"description\": \"Replace blue with green in settings.txt\"}"}}
+{"type":"tool/result","seq":239,"time":1783279386915,"data":{"turn":1,"step":2,"callId":"call_00_SvvpTh6bWybYXoO77NHg8535","content":[{"type":"text","text":"(no output)"}],"isError":false},"sourceEventSeqs":[238],"surfaceOp":"append"}
 {"type":"step/end","seq":240,"time":1783279386916,"data":{"turn":1,"step":2}}
 {"type":"step/start","seq":241,"time":1783279386916,"data":{"turn":1,"step":3}}
 {"type":"assistant/chunk","seq":242,"time":1783279388121,"data":{"turn":1,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.golden.jsonl b/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.golden.jsonl
index 826dbf5eaa..0b6d5dfe33 100644
--- a/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.golden.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.golden.jsonl
@@ -137,7 +137,7 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" use"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" bash"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" with"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" sed"}}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" perl"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" to"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" replace"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" \""}}}}
@@ -152,8 +152,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" the"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_SvvpTh6bWybYXoO77NHg8535","title":"sed -i 's/blue/green/g' settings.txt","kind":"execute","status":"in_progress","rawInput":"sed -i 's/blue/green/g' settings.txt","content":[{"type":"content","content":{"type":"text","text":"Replace blue with green in settings.txt"}}]}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_SvvpTh6bWybYXoO77NHg8535","status":"completed","content":[{"type":"content","content":{"type":"text","text":"```console\n[stderr]\nsed: 1: \"settings.txt\n\": unterminated substitute pattern\n[exit code: 1]\n```"}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_SvvpTh6bWybYXoO77NHg8535","title":"perl -0pi -e 's/blue/green/g' settings.txt","kind":"execute","status":"in_progress","rawInput":"perl -0pi -e 's/blue/green/g' settings.txt","content":[{"type":"content","content":{"type":"text","text":"Replace blue with green in settings.txt"}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_SvvpTh6bWybYXoO77NHg8535","status":"completed","content":[{"type":"content","content":{"type":"text","text":"```console\n(no output)\n```"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" bash"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" command"}}}}