Claude Code, Skill
Langfuse Mcp
Langfuse observability - query traces, debug exceptions, analyze sessions, manage prompts via MCP tools
Compatibility: Not stated.
Grade B
Minor issues only, no Medium or High. Worth a quick look at the findings below before installing.
Not a guarantee. A hygiene check of the source at the commit shown, not a security audit.
Rescanned at commit 3d165608eedf, unchanged since the check below.
NETWORK_NO_FIXED_HOST SECRETS_PATH_DOTENV INSTALL_DOCUMENTED_INSTALLER OBFUSCATION_FILE_OVER_READ_CAP
Why this grade
- NETWORK_NO_FIXED_HOST Low
Makes a network call whose host is not written as a fixed address.
langfuse_mcp/__main__.py, line 2484
trace_id: str = Field(..., description="The ID of the trace to fetch (unique identifier string)"), - SECRETS_PATH_DOTENV Low
Mentions a .env file.
.gitleaks.toml, line 158
description = "Hardcoded credentials in .env files" - INSTALL_DOCUMENTED_INSTALLER Note
Documentation shows an installer that pipes a download into a shell.
CONTRIBUTING.md, line 15
curl -sSf https://astral.sh/uv/install.sh | bash - OBFUSCATION_FILE_OVER_READ_CAP Note
A file was over the read cap and was not fully read.
langfuse_mcp/__main__.py, line 1
"""MCP integration for Langfuse SDK.
Any High, or two or more Medium findings, give D. One Medium gives C. Low findings or a security Note give B. Each code names a finding behind the letter.
Grades are a hygiene check of the source at the commit shown, on the date checked, not a security audit or a guarantee. The free directory grades are automated. Before release, a PlugVet engineer reviews every paid report and any grade we hold back, including all F grades, against the source code and the evidence we quote.
What was checked
Plain notes from the hygiene checks.
Permissions
Pass
No shell or command execution found, and no extra permission was declared.
Install and update
Note
The docs document an installer that pipes a download into a shell.
INSTALL_DOCUMENTED_INSTALLER
CONTRIBUTING.md, line 15
curl -sSf https://astral.sh/uv/install.sh | bash
Network
Concern
can reach a host that is not written as a fixed address.
NETWORK_NO_FIXED_HOST
langfuse_mcp/__main__.py, line 2484
trace_id: str = Field(..., description="The ID of the trace to fetch (unique identifier string)"),
langfuse_mcp/__main__.py, line 2512
trace_id: The ID of the trace to fetch (unique identifier string)
langfuse_mcp/__main__.py, line 2684
observation_id: str = Field(..., description="The ID of the observation to fetch (unique identifier string)"),
Show more
langfuse_mcp/__main__.py, line 2699
observation_id: The ID of the observation to fetch (unique identifier string)
langfuse_mcp/__main__.py, line 3860
description="Label to fetch (e.g., 'production', 'staging'). Mutually exclusive with version.",
langfuse_mcp/__main__.py, line 3875
label: Optional label to fetch (e.g., 'production'). Cannot be used with version.
langfuse_mcp/__main__.py, line 3963
description="Label to fetch (e.g., 'production', 'staging'). Mutually exclusive with version.",
skills/langfuse/references/tool-reference.md, line 342
| `label` | string | No | null | Label to fetch (e.g., "production"). Mutually exclusive with version. |
Secrets
Concern
reads a credential or environment file.
SECRETS_PATH_DOTENV
.gitignore, line 128
# Environments
.gitleaks.toml, line 158
description = "Hardcoded credentials in .env files"
.gitleaks.toml, line 160
path = '''(.*?)\.env(\..*)?$'''
Show more
.gitleaks.toml, line 168
'''\.env\.example$''',
.gitleaks.toml, line 169
'''\.env\.sample$''',
.gitleaks.toml, line 170
'''\.env\.template$''',
CHANGELOG.md, line 293
- MCP CLI now reads Langfuse credentials (`public_key`, `secret_key`, `host`) from a `.env` file or environment variables by default, keeping CLI flags optional
CHANGELOG.md, line 300
- Environment variable support for credentials via `.env` files
Agent instructions
Pass
No instruction to ignore earlier instructions or to hide a step.
Obfuscation
Note
a file was over the read cap and was not fully read.
OBFUSCATION_FILE_OVER_READ_CAP
langfuse_mcp/__main__.py, line 1
"""MCP integration for Langfuse SDK.
Licence
Pass
A licence file is present (LICENSE).
Maintainer activity
Pass
The latest commit is within the last 365 days.
Note
Hygiene check of commit 3d165608eedf. The docs document an installer that pipes a download into a shell. can reach a host that is not written as a fixed address. reads a credential or environment file. a file was over the read cap and was not fully read.
Date and source
Date checked:
github.com
Commit graded: 3d165608eedfd9f0f93051f53dec1f8aabf29624
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