Skills/PyPI/mcp-s3

mcp-s3@1.1.0

VERIFIED· not started

Publisher claims: "MCP S3 File Uploader - A Model Context Protocol server for S3 uploads" Observed in sandbox: no network, touches nothing outside the project, writes no memory.

Registry PyPI (MCP server)Publisher dayongd1 · publishing for 462 daysInstalls 42Last detonated 6d ago
$claude mcp add mcp-s3 -- uvx mcp-s3
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Coverage

Not started: dependency install failed; the server itself was not observed.
Tested
the dependency install step · every file read, file written and host contacted by what ran
Not tested
server startup · the tool list · tool behavior

What this means for the label: Verified here covers what ran. The server's tools were not exercised with a real credential, so nothing about their behavior is asserted; the credential summary below says what to do with that.

Before you give it your token

It will ask for
AWS_ACCESS_KEY_IDAWS_SECRET_ACCESS_KEYConfiguration, not credentials: AWS_DEFAULT_REGION, S3_BUCKET_NAME
Where it talks to
no vendor host named in the code
What the honeypot saw
no credential files read · no network
What we could not test
server startup · the tool list · tool behavior

Connect it with a scoped credential, under the guard. It asks for AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY and talks to its vendor. Give the credential to the guard, not the server: the value never enters the server's environment and only travels to the host you bind. What the tools do with a real credential was not observed.

$vet-skills run --net declared -- uvx mcp-s3

Never paste a credential into a chat, a ticket or a report, including ours. How the guard holds it.

Is [email protected] safe to install?

KillerSkills ran it in the KillerSkills honeypot sandbox (2 scenarios; not started: dependency install failed; the server itself was not observed) on 2026-11-08 and scored it 87/100 (Verified). In what ran, nothing we could detect went wrong: no undeclared network egress, no credential reads, no persistent instruction writes. What it does with a real credential was not observed; the static findings and the publisher carry the rest of the score. Summary: no network, touches nothing outside the project, writes no memory.

Behavior trace

Honeypot run · 0 s · 2 scenarios · 0 deviations
t+CategoryObserved action
0.0sprocessno install scripts in bundle
0.2sprocessdependency install exit 1 ·
0.2sclaimednot started: dependency install failed (exit 1); the server itself was not observed
0.2sprocessscript backend runs setup only
0.2sprocessno install scripts to re-run

Static findings

HIGH
Access to sensitive file pathsmcp_s3.py:20 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system files# Load environment variables from .env fileFix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05
HIGH
Access to sensitive file pathsmcp_s3.py:25 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system filesparser.add_argument("--bucket", help="Target S3 bucket name (overrides .env)")Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05
HIGH
Access to sensitive file pathsmcp_s3.py:34 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system filesraise ValueError("S3 bucket name must be provided via --bucket argument or S3_BUCKET_NAME in .env file")Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05

Cost to the agent

Instructions loaded
≈51 tok
1 file · 10 in bundle
Tool list per prompt
≈0 tok
0 tools · 0 per tool
Handshake
no reply
launch to tools/list, stdio
Undocumented tools
0
description under 20 chars · avg 0

Tokens estimated at four characters each. The tool list is re-read by the agent on every turn, so it is the number to compare between servers that do the same job: ranked across the index.

Known vulnerabilities

No advisories in OSV for mcp-s3@1.1.0 as of 6d ago. This is the package itself, not its dependencies.