Description
Some providers appear to return a non-standard finish reason:
finish_reason: "model_context_window_exceeded"
Based on internet search, this was introduced on Anthropic side, and z.ai seems to follow the same behavior when context is too long.
In OpenCode, this finish reason is currently treated as unknown (instead of length), which can cause the session loop to continue rather than stop/compact, resulting in repeated/infinite loops sending request.
This is one of the repeated assistant message exported from session:
{
"message": {
"role": "assistant",
"time": {
"created": 1774204420869,
"completed": 1774204423742
},
"parentID": "msg_d16d2a7f7001GyKBIDcFE3dGOY",
"modelID": "glm-5-turbo",
"providerID": "zhipuai-coding-plan",
"mode": "normal",
"agent": "normal",
"path": {
"cwd": "/home/hmsy/workspace",
"root": "/home/hmsy/workspace"
},
"cost": 0,
"tokens": {
"input": 0,
"output": 0,
"reasoning": 0,
"cache": {
"read": 0,
"write": 0
}
},
"finish": "unknown",
"id": "msg_d16d30305001Nyw0BNeLsTjxCe",
"sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT"
},
"parts": [
{
"type": "step-start",
"snapshot": "51df3df3638f2d50ef5530301f1f3889bcf12c29",
"id": "prt_d16d30e2c001TYpfLIMd5SSeof",
"sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT",
"messageID": "msg_d16d30305001Nyw0BNeLsTjxCe"
},
{
"type": "step-finish",
"reason": "unknown",
"snapshot": "51df3df3638f2d50ef5530301f1f3889bcf12c29",
"cost": 0,
"tokens": {
"input": 0,
"output": 0,
"reasoning": 0,
"cache": {
"read": 0,
"write": 0
}
},
"id": "prt_d16d30e2d001V047uR4bXcaluN",
"sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT",
"messageID": "msg_d16d30305001Nyw0BNeLsTjxCe"
}
]
}This is the request and response of z.ai
References:
OpenClaw already handled this case: openclaw/openclaw#35934
Link OpenCode issue: #15778
Expected behavior:
Treat model_context_window_exceeded as length (or equivalent overflow handling).
Stop current generation and trigger normal overflow/compaction flow, instead of continuing with unknown.
Plugins
no
OpenCode version
v1.3.0
Steps to reproduce
No response
Screenshot and/or share link
z.ai model context limit reached
Operating System
Linux
Terminal
Alacritty
Description
Some providers appear to return a non-standard finish reason:
finish_reason: "model_context_window_exceeded"Based on internet search, this was introduced on Anthropic side, and z.ai seems to follow the same behavior when context is too long.
In OpenCode, this finish reason is currently treated as
unknown(instead oflength), which can cause the session loop to continue rather than stop/compact, resulting in repeated/infinite loops sending request.This is one of the repeated assistant message exported from session:
{ "message": { "role": "assistant", "time": { "created": 1774204420869, "completed": 1774204423742 }, "parentID": "msg_d16d2a7f7001GyKBIDcFE3dGOY", "modelID": "glm-5-turbo", "providerID": "zhipuai-coding-plan", "mode": "normal", "agent": "normal", "path": { "cwd": "/home/hmsy/workspace", "root": "/home/hmsy/workspace" }, "cost": 0, "tokens": { "input": 0, "output": 0, "reasoning": 0, "cache": { "read": 0, "write": 0 } }, "finish": "unknown", "id": "msg_d16d30305001Nyw0BNeLsTjxCe", "sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT" }, "parts": [ { "type": "step-start", "snapshot": "51df3df3638f2d50ef5530301f1f3889bcf12c29", "id": "prt_d16d30e2c001TYpfLIMd5SSeof", "sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT", "messageID": "msg_d16d30305001Nyw0BNeLsTjxCe" }, { "type": "step-finish", "reason": "unknown", "snapshot": "51df3df3638f2d50ef5530301f1f3889bcf12c29", "cost": 0, "tokens": { "input": 0, "output": 0, "reasoning": 0, "cache": { "read": 0, "write": 0 } }, "id": "prt_d16d30e2d001V047uR4bXcaluN", "sessionID": "ses_2e9440126ffeOGeX4DKrphB4tT", "messageID": "msg_d16d30305001Nyw0BNeLsTjxCe" } ] }This is the request and response of z.ai
References:
OpenClaw already handled this case: openclaw/openclaw#35934
Link OpenCode issue: #15778
Expected behavior:
Treat
model_context_window_exceededaslength(or equivalent overflow handling).Stop current generation and trigger normal overflow/compaction flow, instead of continuing with unknown.
Plugins
no
OpenCode version
v1.3.0
Steps to reproduce
No response
Screenshot and/or share link
z.ai model context limit reached
Operating System
Linux
Terminal
Alacritty