Add dynamic agent selection to configure

[codeprakhar25]

Summary

• Add interactive agent selection for agentdiff configure, with detected/not-detected labels and Gemini/Antigravity left optional by default.
• Add non-interactive --all and --agents paths while preserving existing --no-* skip flags.
• Update README configure examples and behavior notes.

Closes #10

Test plan

• cargo test
• cargo run --bin agentdiff -- configure --help
• cargo run --bin agentdiff -- configure --agents nope fails before writing setup files

[greptile-apps]

Greptile Summary

This PR adds interactive agent selection to agentdiff configure via a dialoguer multi-select picker, plus non-interactive --all and --agents escape hatches, while preserving existing --no-* skip flags. The AgentTarget/AgentSelection abstraction is clean and the refactor to pass &ConfigureArgs directly simplifies the call site significantly. The three P2 findings are all in src/configure/mod.rs: a silent behavior change for --no-mcp when Claude is de-selected, an inconsistency between interactive and non-interactive default selections, and a Copilot false-positive detection heuristic.

Confidence Score: 4/5

Safe to merge with minor caveats; no data loss or security risk, but three P2 issues in configure logic worth addressing.

All findings are P2 (non-blocking). The --no-mcp behavior change is a subtle breaking change for an edge-case workflow, the non-interactive vs interactive default inconsistency may produce noisy CI output, and the Copilot detection false positive is cosmetic. Core attribution logic is untouched.

src/configure/mod.rs — resolve_agent_selection, detect_agents, and the MCP gate logic.

Important Files Changed

Filename	Overview
src/configure/mod.rs	Core refactor introducing dynamic agent selection; contains a behavior change for --no-mcp, an inconsistency between interactive and non-interactive defaults, and a false-positive Copilot detection heuristic.
src/cli.rs	Adds --all and --agents flags to ConfigureArgs; straightforward and correct.
src/main.rs	Simplified configure dispatch to pass args struct directly; clean change.
README.md	Updated configure examples and behavior notes for interactive/non-interactive modes; accurate.
Cargo.toml	Adds dialoguer 0.12.0 with default-features disabled; appropriate minimal dependency.
Cargo.lock	Lock file updated to include dialoguer, console, shell-words, encode_unicode, unicode-width; all from crates.io.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[agentdiff configure] --> B{--all AND --agents?}
    B -- yes --> ERR[bail! mutually exclusive]
    B -- no --> C{--all?}
    C -- yes --> SEL_ALL[AgentSelection::all]
    C -- no --> D{--agents list?}
    D -- yes --> PARSE[parse names via AgentTarget::from_name\nbail on unknown agent]
    PARSE --> SEL_EXP[AgentSelection from explicit list]
    D -- no --> E{stdin is_terminal?}
    E -- yes --> PROMPT[prompt_agent_selection\ndetect_agents + MultiSelect picker\ndefault = default_selected AND detected]
    E -- no --> SEL_REC[AgentSelection::recommended\nall except Antigravity]
    SEL_ALL --> FLAGS[apply_skip_flags\nno_claude/cursor/codex/windsurf/opencode/copilot/antigravity]
    SEL_EXP --> FLAGS
    PROMPT --> FLAGS
    SEL_REC --> FLAGS
    FLAGS --> RUN[run configure steps per selection flags]
    RUN --> MCP{selection.claude AND NOT no_mcp?}
    MCP -- yes --> CMCP[step_configure_mcp_claude]
    MCP -- no --> SKIP_MCP[skip MCP]

Loading

Comments Outside Diff (1)

1. src/configure/mod.rs, line 390-398 (link)

   Copilot detection produces false positives

   detect_agents marks Copilot as "detected" if any VS Code extensions directory exists:

   if [".vscode/extensions", ".vscode-server/extensions", ".vscode-insiders/extensions"]
       .iter()
       .any(|path| home.join(path).exists())
   {
       detected.push(AgentTarget::Copilot);
   }

   Any VS Code user who does not have the GitHub Copilot extension installed will see it labeled (detected, default) in the interactive picker and it will be pre-selected. Checking for the Copilot extension directory (e.g. extensions/github.copilot-*) would make the heuristic accurate.

_{Reviews (1): Last reviewed commit: "feat: add dynamic agent selection to con..." | Re-trigger Greptile}

[greptile-apps]

--no-claude now silently skips MCP configuration

The old code gated Claude and MCP independently:

// old
if !no_claude { claude::step_configure_claude(config)?; }
if !no_mcp    { claude::step_configure_mcp_claude()?;  }

The new code ties MCP to selection.claude:

if selection.claude && !args.no_mcp {
    claude::step_configure_mcp_claude()?;
}

selection.claude becomes false via the interactive picker (user de-selects Claude), --no-claude, or --agents <list-without-claude>. In all those cases MCP is now silently skipped even if --no-mcp was not supplied. Anyone who previously ran --no-claude expecting MCP to still be registered will now silently get neither. If the intent is to permanently couple them, the change should be documented explicitly.

[greptile-apps]

Non-interactive mode configures all agents regardless of installation

When stdin is not a terminal (CI, scripts), AgentSelection::recommended() enables every agent except Antigravity unconditionally:

fn recommended() -> Self {
    Self { antigravity: false, ..Self::all() }
}

In contrast, the interactive picker only pre-checks agents that are both default_selected and present on disk (detected.contains(agent)). A CI runner that calls agentdiff configure without flags will attempt to configure Cursor, Codex, Windsurf, OpenCode, and Copilot even when none of those tools are installed. The individual configure steps may handle missing dirs gracefully, but the inconsistency between interactive and non-interactive defaults is surprising and may produce noisy output in automated contexts.