feat(copilot): prompt flag fix + ACP provider support#31
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EmmittJ wants to merge 5 commits intogastownhall:mainfrom
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feat(copilot): prompt flag fix + ACP provider support#31EmmittJ wants to merge 5 commits intogastownhall:mainfrom
EmmittJ wants to merge 5 commits intogastownhall:mainfrom
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Copilot CLI expects prompts via `-p`/`--prompt <text>`, not as a bare positional argument. Switch the built-in copilot provider from PromptMode "arg" to "flag" with PromptFlag "--prompt". Wire PromptMode and PromptFlag through runtime.Config so the tmux adapter inserts the flag before the prompt payload in all code paths (temp-file, inline, and fallback). Guard the ResolvedProvider dereference in templateParamsToConfig with a nil check to prevent a panic when no provider is resolved. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Enable Copilot as a first-class ACP provider, bringing it to parity with Claude for Gas City orchestration: - SupportsACP: true — Copilot speaks ACP (JSON-RPC 2.0 over stdio) - ACPArgs: ["--acp"] — new ProviderSpec field for ACP-specific CLI flags, appended to the command when session = "acp". Unlike Claude (which auto-detects pipe mode), Copilot requires an explicit --acp flag. - ResumeFlag: "--resume" with ResumeStyle: "flag" for session resume - PermissionModes: map unrestricted → --yolo - OptionsSchema: permission_mode and model selectors for Mission Control Wire ACPArgs through the full config pipeline: ProviderSpec → compose (deepMergeProvider) → resolve (specToResolved) → ResolvedProvider → template_resolve (command construction) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
copilot --acp starts a TCP server waiting for connections, not a stdio-based JSON-RPC process. The --stdio flag switches it to use stdin/stdout for ACP communication, which is what Gas City's ACP adapter expects when piping JSON-RPC messages. Without --stdio, Gas City's ACP handshake hangs indefinitely until the handshake_timeout fires, causing sessions to appear stuck in 'creating' state. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…quest Copilot's ACP implementation requires protocolVersion (integer) in the initialize params — omitting it returns a -32603 Internal error: 'expected number, received undefined'. This caused every ACP handshake to silently fail and sessions to hit the 30s handshake timeout. Also add clientCapabilities (terminal + fs) to match what the go-acp library and Legion's vessel-driver send. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…notification Copilot requires both 'cwd' and 'mcpServers' fields in session/new params (null or empty object returns -32603). Add SessionNewParams struct with required fields; mcpServers sent as empty array when none configured. Remove the 'initialized' notification between initialize and session/new — ACP does not define this step (it's an MCP concept) and Copilot ignores it. Bump default handshake_timeout from 30s to 60s since session/new triggers a model list fetch from GitHub API (~5s on good networks). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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@julianknutsen this should be good for review. If you would like me to split anything out, let me know. |
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Summary
Brings the built-in Copilot provider to parity with Claude as a first-class ACP provider in Gas City.
Changes
Fix:
--promptflag deliveryThe Copilot provider was configured with
prompt_mode = "arg", passing prompts as bare positional arguments. Copilot CLI expects--prompt <text>instead.PromptMode: "arg"→PromptMode: "flag",PromptFlag: "--prompt"PromptMode/PromptFlagfields toruntime.ConfigPromptMode/PromptFlagfromResolvedProviderintoruntime.Config(nil-guarded)Feat: ACP support for Copilot
SupportsACP: true,ACPArgs: ["--acp", "--stdio"],ResumeFlag,ResumeStyle,PermissionModes,OptionsSchemato copilot builtin; addACPArgs []stringfield toProviderSpecandResolvedProvideracp_argsslice merging indeepMergeProviderACPArgsinspecToResolvedACPArgsto command whensession = "acp"Fix: ACP protocol correctness for Copilot
Copilot's ACP server uses strict schema validation. Several protocol issues required fixing:
--stdioflag:copilot --acpalone starts a TCP server;--stdioswitches it to JSON-RPC over stdin/stdout (required for Gas City's pipe-based adapter). This flag is not shown incopilot --helpbut is accepted.protocolVersion: Added integer field (1) toInitializeParams— omitting it causes-32603 Internal error: expected number, received undefinedsession/newparams: Copilot requires bothcwd(string) andmcpServers(array) — sendingnullor{}returns a validation error; addedSessionNewParams+MCPServerstructs and wiredworkDirthrough to the handshakeinitializednotification: Gas City was sending an MCP lifecycle notification betweeninitializeandsession/new; this is not part of the ACP spec and Copilot hangs on itsession/newwhich takes ~5sTesting
Verified end-to-end:
gc session new mayorwithsession = "acp"successfully starts a Copilot ACP process (copilot --yolo --acp --stdio --prompt ...) and transitions the session toawake.