Agent skill

Verify Success After Unknown Error

Verify task completion by checking filesystem state when executecodesandbox or runshell return misleading unknown errors

MITAuto-check passed

Install Verify Success After Unknown Error

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .claude/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .claude/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .claude/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .agents/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .agents/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .agents/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .cursor/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .cursor/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/HKUDS/OpenSpace.git --path benchmarks/gdpval/skills/verify-success-after-unknown-error

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .gemini/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .gemini/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .github/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .github/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .github/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install HKUDS/OpenSpace verify-success-after-unknown-error --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/HKUDS/OpenSpace.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/benchmarks/gdpval/skills/verify-success-after-unknown-error .opencode/skills/verify-success-after-unknown-error && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "verify-success-after-unknown-error" agent skill from https://github.com/HKUDS/OpenSpace/tree/main/benchmarks/gdpval/skills/verify-success-after-unknown-error into .opencode/skills/verify-success-after-unknown-error/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "verify-success-after-unknown-error", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: verify-success-after-unknown-error
GitHub stars: 7.8k
Token cost: ~1.1k tokens
SKILL.md length: 220 words
Files: 2
Skills in repo: 199
Repo updated: Aug 12, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Verify task completion by checking filesystem state when executecodesandbox or runshell return misleading unknown errors

Works in 3 steps: Check Expected Output Files → Validate File Content/State → Decision Logic
SKILL.md covers Purpose, When to Apply, Verification Steps and Code Example: Complete Pattern, plus 4 more sections
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Verify Success After Unknown Error is an agent skill from HKUDS/OpenSpace. Verify task completion by checking filesystem state when executecodesandbox or runshell return misleading unknown errors

Its SKILL.md is about 1.1k tokens, which your agent loads only when the skill is triggered. The skill folder holds 1 other file.

The repository describes itself as: "OpenSpace: The Skill Management Layer for AI Agents" -- https://open-space.cloud/. The licence is MIT.

Example prompts

“/verify-success-after-unknown-error”

Requirements

Python 3

Workflow steps

3 steps, taken from the step headings in SKILL.md.

Check Expected Output Files
Validate File Content/State
Decision Logic

What it can do on your machine

Read from SKILL.md and the folder at commit 3827781. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are python and bash).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Verify Success After Unknown Error loads about 1.1k tokens when it runs. Until then it costs about 40 tokens; SKILL.md has 220 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~40
When it runs · the whole SKILL.md, loaded when a task matches: ~1.1k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from HKUDS/OpenSpace at commit 3827781, republished under its MIT licence (© HKUDS). 220 words, ~1,150 tokens.

Download SKILL.mdSave it as .claude/skills/verify-success-after-unknown-error/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.

name: verify-success-after-unknown-error
description: Verify task completion by checking filesystem state when execute_code_sandbox or run_shell return misleading unknown errors

Verify Success After Unknown Error

Purpose

When execute_code_sandbox or run_shell return "unknown error" messages, the underlying task may have actually succeeded. This skill provides a systematic approach to verify actual completion before assuming failure and retrying unnecessarily.

When to Apply

Use this pattern when:

execute_code_sandbox returns "unknown error" but your code may have completed
run_shell fails with unclear error messages
File creation, modification, or transformation tasks report errors
The error message is generic/unspecified rather than a clear failure reason

Verification Steps

Step 1: Check Expected Output Files

After receiving an unknown error, immediately verify if expected files were created:

python

# Example: Verify file creation after execute_code_sandbox
from tools import list_dir, read_file

# List directory to check if files exist
files = list_dir(path="/workspace/output")
print(files)

# Check specific file existence
expected_files = ["report.pdf", "data.xlsx"]
for f in expected_files:
    try:
        content = read_file(filetype="pdf", file_path=f"/workspace/output/{f}")
        print(f"✓ {f} exists and is readable")
    except:
        print(f"✗ {f} not found or unreadable")

Step 2: Validate File Content/State

Don't just check existence — verify the files have expected content:

python

# For spreadsheets
file_content = read_file(filetype="xlsx", file_path="/workspace/output/schedule.xlsx")
# Verify expected sheets, columns, or data exist

# For text/json files
file_content = read_file(filetype="txt", file_path="/workspace/output/result.json")
# Parse and validate structure

# For directories
dir_contents = list_dir(path="/workspace/output")
# Verify expected number of files or specific files exist

Step 3: Decision Logic

IF expected files exist AND content is valid:
    → Task succeeded despite error message
    → Proceed to next step without retry
    
ELIF files exist but content is incomplete:
    → Partial success, may need targeted fix
    
ELSE (files missing or corrupted):
    → True failure, retry or debug required

Code Example: Complete Pattern

python

def execute_with_verification(code, expected_files):
    """Execute code and verify success even if error returned."""
    
    # Attempt execution
    result = execute_code_sandbox(code=code)
    
    # Check for unknown/generic errors
    if "unknown error" in result.get("output", "").lower() or result.get("error"):
        print("Received error, verifying actual outcome...")
        
        # Verify filesystem state
        all_present = True
        for f in expected_files:
            try:
                list_dir(path=f"/workspace/{f}")  # or appropriate path
                print(f"✓ {f} verified")
            except:
                print(f"✗ {f} missing")
                all_present = False
        
        if all_present:
            print("Task completed successfully despite error message")
            return {"status": "success_verified", "files": expected_files}
        else:
            print("True failure - files not created")
            return {"status": "failed", "error": result.get("error")}
    
    return {"status": "success", "output": result.get("output")}

Shell Command Example

bash

# After run_shell returns error, verify with:
ls -la /workspace/output/
test -f /workspace/output/result.pdf && echo "File exists" || echo "File missing"
file /workspace/output/result.pdf  # Verify file type is correct

Benefits

Saves iterations: Avoids unnecessary retries when task already succeeded
Handles tool bugs: Works around sandbox/shell tool reporting issues
Faster completion: Move forward immediately when verification passes
Clearer debugging: Distinguishes true failures from false positives

Anti-Patterns to Avoid

✗ Immediately retrying on any error without verification
✗ Assuming "unknown error" means complete failure
✗ Only checking file existence without validating content
✗ Skipping verification for "minor" tasks (any file output should be verified)

list_dir — Check directory contents
read_file — Validate file content and accessibility
execute_code_sandbox — Primary execution tool this pattern supports
run_shell — Shell execution tool this pattern supports

Files

SKILL.md and 1 other file in benchmarks/gdpval/skills/verify-success-after-unknown-error of HKUDS/OpenSpace.

SKILL.md
.skill_id

Open the folder on GitHubat commit 3827781

Compare with similar skills

Verify Success After Unknown Error next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Verify Success After Unknown Error compared with similar skills
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Verify Success After Unknown Error this skillHKUDS/OpenSpace	7.8k	—	~1.1k	Automated safety check: Pass	MIT	1 mo ago
Fact Check X Completesickn33/agentic-awesome-skills	47k	1 repos	~2.3k	Automated safety check: Pass	Apache-2.0	yesterday
Completion Checkparcadei/Continuous-Claude-v3	3.9k	1 repos	~733	Automated safety check: Pass	MIT	8 mo ago
Check PRpaperclipai/paperclip	99k	—	~3.6k	Automated safety check: Pass	MIT	today
Checkdavepoon/buildwithclaude	3.6k	—	~680	Automated safety check: Pass	MIT	yesterday
Fact Check X Unifiedsickn33/agentic-awesome-skills	47k	1 repos	~1.7k	Automated safety check: Pass	Apache-2.0	yesterday

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Questions about Verify Success After Unknown Error

What does Verify Success After Unknown Error do?

Verify task completion by checking filesystem state when executecodesandbox or runshell return misleading unknown errors. Verify Success After Unknown Error is an agent skill from HKUDS/OpenSpace.

How do I install Verify Success After Unknown Error in Claude Code?

Run `npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a claude-code`. Or copy the skill folder (benchmarks/gdpval/skills/verify-success-after-unknown-error in HKUDS/OpenSpace) into .claude/skills/verify-success-after-unknown-error in your project. Claude Code loads it when a task matches its description.

How do I install Verify Success After Unknown Error in Codex?

Run `npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a codex`. Or copy the skill folder (benchmarks/gdpval/skills/verify-success-after-unknown-error in HKUDS/OpenSpace) into .agents/skills/verify-success-after-unknown-error in your project. Codex loads it when a task matches its description.

Can I use Verify Success After Unknown Error in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add HKUDS/OpenSpace --skill verify-success-after-unknown-error -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/verify-success-after-unknown-error, .gemini/skills/verify-success-after-unknown-error, .github/skills/verify-success-after-unknown-error and .opencode/skills/verify-success-after-unknown-error in your project.

What does Verify Success After Unknown Error need to run?

SKILL.md names no scripts, command-line tools or credentials: Verify Success After Unknown Error is instructions for the agent only. Our summary lists: Python 3.

Does Verify Success After Unknown Error access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Verify Success After Unknown Error safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Verify Success After Unknown Error use?

Verify Success After Unknown Error is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Verify Success After Unknown Error use?

About 1.1k tokens (SKILL.md is roughly 4.6k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Verify Success After Unknown Error?

Skills that share tags, products or a category with Verify Success After Unknown Error: Fact Check X Complete (sickn33/agentic-awesome-skills, 47k stars), Completion Check (parcadei/Continuous-Claude-v3, 3.9k stars), Check PR (paperclipai/paperclip, 99k stars) and Check (davepoon/buildwithclaude, 3.6k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Verify Success After Unknown Error?

HKUDS (a GitHub organization) maintains it in HKUDS/OpenSpace, which has 7,754 GitHub stars. The repository holds 199 skills in this directory. The repository was last updated on August 12, 2026.

Source: HKUDS/OpenSpace on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Verify Success After Unknown Error

Facts

At a glance

What it does

Example prompts

Requirements

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Verify Success After Unknown Error

Purpose

When to Apply

Verification Steps

Step 1: Check Expected Output Files

Step 2: Validate File Content/State

Step 3: Decision Logic

Code Example: Complete Pattern

Shell Command Example

Benefits

Anti-Patterns to Avoid

Related Tools

Files

Compare with similar skills

Similar skills

More from HKUDS/OpenSpace

Questions about Verify Success After Unknown Error