[BUG][v0.0.7] DAG executor hardcodes `sh -c`, breaking command tasks on typical Windows setups

[topwork-28]

Project

cortex

Description

The DAG command executor invokes shell commands via Command::new("sh").arg("-c").arg(cmd). On standard Windows environments without a Unix shell in PATH, this fails before the task command can run.

System Information

Version: 0.1.0

## Operating System
OS: Windows 10/11
Arch: x86_64

## Build Environment
Rust: rustc 1.93.1 (01f6ddf75 2026-02-11)
Target: x86_64

Screenshots

https://github.com/techforgeworks-sudo/images/blob/main/8_40.png

Steps to Reproduce

1. On Windows, create a DAG spec with a command task (example: command: echo Hello).
2. Run cortex dag run --file tasks.yaml.
3. Observe failure to execute the command.

Expected Behavior

Use platform-appropriate shell invocation on Windows (e.g., cmd /C or PowerShell) or a shell abstraction that supports both OS families.

Actual Behavior

Executor invokes sh, which may be unavailable on Windows hosts.

Additional Context

• Hardcoded invocation: src/cortex-cli/src/dag_cmd/executor.rs (around lines 79-81).

[atlas-cortex]

✅ Validation Summary — Issue #53151

All validation checks passed. 1/17 code rules failed | 1 PENALIZE | 14 LLM instructions active

Confidence Score: 4/5

• All validation checks passed. This submission meets the bounty requirements.

Validation Checks

Check	Status	Detail
Media Evidence	✅ Pass	Evidence found and accessible
Spam Detection	✅ Pass	Score: 25% — no spam signals
Duplicate Detection	✅ Pass	No significant overlap with existing issues
Code Verification	✅ Pass	Bug confirmed in source code (confidence: 100%) — The code in src/cortex-cli/src/dag_cmd/executor.rs hardcodes `tokio::process::
Edit History	✅ Pass	No suspicious edits
LLM Evaluation	✅ Pass	All validation checks passed. 1/17 code rules failed

Validation Pipeline

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["Issue #53151"] --> B{"Media Check"}
    B -->|"✅ Found"| C{"Spam Check"}
    C -->|"✅ Clean"| D{"Duplicate Check"}
    D -->|"✅ Unique"| CV{"Code Verify"}
    CV -->|"✅ Confirmed"| E{"Edit History"}
    E -->|"✅ Normal"| F{"LLM Evaluation"}
    F -->|"✅ Valid"| G["✅ Approved"]
    style G fill:#51cf66,color:#fff

Loading

Raw Evidence

{
  "media": {
    "hasMedia": true,
    "accessible": true,
    "urls": [
      "https://github.com/techforgeworks-sudo/images/blob/main/8_40.png"
    ],
    "evidence": [
      "Found 1 media URL(s) via markdown parsing",
      "1 URL(s) accessible"
    ]
  },
  "spam": {
    "overallScore": 0.2529940119760479,
    "details": "template=0.26 (2 recent issues compared); burst=0.50 (3 issues in 2h window); parity=0.00; overall=0.25 (threshold=0.7)"
  },
  "duplicate": {
    "isDuplicate": false,
    "similarity": 0.5740375910910973,
    "topSimilar": [
      {
        "issueNumber": 51245,
        "title": "[BUG] [v0.0.7] `cortex dag run` silently ignores task-level `env:` section — environment variables never passed to command execution",
        "similarity": 0.5740375910910973
      },
      {
        "issueNumber": 52613,
        "title": "[BUG] [v0.0.7] DAG YAML `working_dir` field is parsed but silently ignored — task runs in home directory instead of specified path",
        "similarity": 0.5591406257297487
      },
      {
        "issueNumber": 52969,
        "title": "[SECURITY] [v0.1.0] DAG task `command` executed via **`sh -c`** — untrusted DAG files can run arbitrary shell",
        "similarity": 0.5558603288949033
      },
      {
        "issueNumber": 52614,
        "title": "[BUG] [v0.0.7] DAG YAML `env` field is parsed but silently ignored — environment variables not passed to task command",
        "similarity": 0.5540670143842238
      },
      {
        "issueNumber": 52858,
        "title": "[BUG] [v0.0.7] cortex dag create splits normal success output across stderr and stdout",
        "similarity": 0.5502110285589591
      }
    ]
  },
  "editHistory": {
    "fraudScore": 0,
    "editCount": 0,
    "details": "No edits detected"
  },
  "codeVerification": {
    "plausible": true,
    "confidence": 1,
    "reasoning": "The code in `src/cortex-cli/src/dag_cmd/executor.rs` hardcodes `tokio::process::Command::new(\"sh\").arg(\"-c\").arg(cmd)` to execute commands. This will fail on Windows environments where `sh` is not available in the PATH, confirming the bug report.",
    "codeEvidence": "let output = tokio::process::Command::new(\"sh\")\n    .arg(\"-c\")\n    .arg(cmd)\n    .output()\n    .await\n    .context(\"Failed to execute command\")?;",
    "screenshotValid": true,
    "screenshotReasoning": "The screenshot analysis returned valid."
  },
  "rules": {
    "codeResults": {
      "passed": [
        {
          "ruleId": "content.no-profanity",
          "category": "content",
          "severity": "flag",
          "passed": true,
          "message": "Issue should not contain excessive profanity or abusive language",
          "weight": 1
        },
        {
          "ruleId": "content.reasonable-length",
          "category": "content",
          "severity": "flag",
          "passed": true,
          "message": "Issue body should not exceed 15000 characters (possible spam dump)",
          "weight": 1
        },
        {
          "ruleId": "content.has-context",
          "category": "content",
          "severity": "penalize",
          "passed": true,
          "message": "Issue should mention the affected page, component, or URL",
          "weight": 0.2
        },
        {
          "ruleId": "media.require-evidence",
          "category": "media",
          "severity": "require",
          "passed": true,
          "message": "Issue must include at least one screenshot or video URL",
          "weight": 1
        },
        {
          "ruleId": "media.must-be-accessible",
          "category": "media",
          "severity": "require",
          "passed": true,
          "message": "All media URLs must be publicly accessible (HTTP 200)",
          "weight": 1
        },
        {
          "ruleId": "media.no-placeholder-urls",
          "category": "media",
          "severity": "reject",
          "passed": true,
          "message": "Media URLs should not be placeholder or example URLs",
          "weight": 1
        },
        {
          "ruleId": "scoring.suspicious-edits",
          "category": "scoring",
          "severity": "penalize",
          "passed": true,
          "message": "Penalize issues with concerning edit history (fraud score > 0.3)",
          "weight": 0.25
        },
        {
          "ruleId": "spam.high-score-reject",
          "category": "spam",
          "severity": "reject",
          "passed": true,
          "message": "Reject issues with spam score above 0.85",
          "weight": 1
        },
        {
          "ruleId": "spam.generic-title",
          "category": "spam",
          "severity": "penalize",
          "passed": true,
          "message": "Title should not be a generic/template title",
          "weight": 0.4
        },
        {
          "ruleId": "spam.body-is-title-repeat",
          "category": "spam",
          "severity": "penalize",
          "passed": true,
          "message": "Body should not be a simple repetition of the title",
          "weight": 0.5
        },
        {
          "ruleId": "spam.no-ai-filler",
          "category": "spam",
          "severity": "flag",
          "passed": true,
          "message": "Body should not contain obvious AI-generated filler phrases",
          "weight": 1
        },
        {
          "ruleId": "validity.min-body-length",
          "category": "validity",
          "severity": "reject",
          "passed": true,
          "message": "Issue body must be at least 50 characters",
          "weight": 1
        },
        {
          "ruleId": "validity.min-title-length",
          "category": "validity",
          "severity": "reject",
          "passed": true,
          "message": "Issue title must be at least 10 characters",
          "weight": 1
        },
        {
          "ruleId": "validity.no-empty-body",
          "category": "validity",
          "severity": "reject",
          "passed": true,
          "message": "Issue body must not be empty or only whitespace",
          "weight": 1
        },
        {
          "ruleId": "validity.has-steps-or-description",
          "category": "validity",
          "severity": "penalize",
          "passed": true,
          "message": "Issue body should contain structured content (steps, expected/actual behavior)",
          "weight": 0.3
        },
        {
          "ruleId": "validity.not-a-feature-request",
          "category": "validity",
          "severity": "flag",
          "passed": true,
          "message": "Issue should describe a bug, not a feature request",
          "weight": 1
        }
      ],
      "failed": [
        {
          "ruleId": "scoring.duplicate-threshold",
          "category": "scoring",
          "severity": "penalize",
          "passed": false,
          "message": "Issue has moderate similarity to existing issues, suggesting partial overlap.",
          "weight": 0.3
        }
      ]
    },
    "llmInstructions": [
      "Always prioritize concrete evidence (screenshots, videos, URLs) over the quality of the written description. A poorly written report with clear visual proof of a bug is VALID. A beautifully written report with no evidence is INVALID.",
      "A valid bug report must contain enough information for an engineer to reproduce the issue. If the steps to reproduce are missing or impossibly vague (\"it just broke\"), the issue is INVALID.",
      "You MUST call the deliver_verdict function exactly once. Do not output a JSON object manually. Do not output your verdict in plain text. Use the tool.",
      "Be highly suspicious of submissions that follow a rigid template: same structure, same phrasing, with only the page name or URL swapped. These are template-farmed and should be INVALID. Look for: identical sentence structure, placeholder-like descriptions, formulaic \"Steps to Reproduce\".",
      "When similar issues exist, the OLDER issue (lower issue number) always takes precedence. The newer submission is the duplicate, never the other way around.",
      "Confidence scores must be calibrated: use 0.9+ only when evidence is unambiguous and complete. Use 0.5-0.7 when the issue is borderline. Use below 0.5 when you are genuinely uncertain. Never default to 0.5 — commit to a direction.",
      "Do not give the benefit of the doubt. Missing evidence means INVALID. Unclear reproduction steps means INVALID. Inaccessible media means INVALID. The burden of proof is on the submitter.",
      "In the reasoning field, explain your step-by-step analysis BEFORE stating your conclusion. Cover: evidence quality, clarity, spam signals, and duplicate overlap in that order.",
      "Never mention internal scoring thresholds, rule IDs, detection heuristics, or system architecture in the recap field. The recap is public-facing. Keep reasoning technical but recap user-friendly.",
      "If the issue body reads like AI-generated boilerplate (phrases like \"It is important to note\", \"Furthermore\", \"In conclusion\", excessive politeness, no specific technical details), treat it as strong evidence of spam. AI-generated issues with no real bug details are INVALID.",
      "If the pre-computed media check says media URLs exist, verify the description matches what a screenshot would show. If the description talks about a login page but the context suggests the screenshot is of something unrelated, flag this as suspicious.",
      "Never soften a verdict out of sympathy. \"I can see you tried hard but...\" is not acceptable. If the submission does not meet criteria, it is INVALID regardless of apparent effort.",
      "Write your reasoning and recap in a professional, neutral tone. Do not be sarcastic, condescending, or emotional. State facts.",
      "The recap field must be 2-3 sentences maximum. It will be posted as a public comment. No bullet points in recap — use flowing prose."
    ],
    "totalCodeRules": 17,
    "totalLLMRules": 14,
    "hasReject": false,
    "hasFailed": true,
    "penaltyScore": 0.3,
    "summary": "1/17 code rules failed | 1 PENALIZE | 14 LLM instructions active"
  }
}

_{Validated by Atlas • 2026-04-10}

[GreyforgeLabs]

Opened upstream fix: CortexLM/cortex-code#374

Change:

• DAG task execution now selects the shell by platform: cmd.exe /C on Windows, sh -c elsewhere.
• Existing Unix-like behavior is preserved while typical Windows hosts no longer require a Unix sh in PATH.

Validation:

• cargo fmt --package cortex-cli --check
• git diff --check
• cargo check -p cortex-cli --no-default-features --features cortex-tui
• cargo run -p cortex-cli --no-default-features --features cortex-tui --bin Cortex -- dag run --file /tmp/cortex-dag-shell-smoke.yaml --strategy sequential --quiet