debugging-lambda-timeouts

An agent skill by aws, from aws/agent-toolkit-for-aws. Tags: aws, debugging, lambda, performance, troubleshooting.

What it does

Debugs AWS Lambda function timeout failures by systematically analyzing function configuration, CloudWatch logs and metrics, VPC/networking, cold starts, memory constraints, and downstream dependencies to identify root causes with actionable fixes. Use when a Lambda function is timing out or approaching its timeout limit.

Install

With the skills CLI, which installs into Claude Code, Codex, Cursor and other agents:

npx skills add aws/agent-toolkit-for-aws --skill debugging-lambda-timeouts

Or copy the skill folder into Claude Code's skills directory by hand (~/.claude/skills for every project, or .claude/skills inside one):

git clone --depth 1 https://github.com/aws/agent-toolkit-for-aws
cp -r agent-toolkit-for-aws/skills/specialized-skills/serverless-skills/debugging-lambda-timeouts ~/.claude/skills/debugging-lambda-timeouts

Safety box score

Grade B, low risk: 18 of 100 risk points, rated 2026-09-25. The grade rates what the skill and its scripts can reach on the machine of whoever installs it, across eight categories from shell execution to secrets access. How the score works.

This skill is a read-only AWS troubleshooting workflow for Lambda timeout failures. It pulls Lambda configuration, CloudWatch metrics/logs, and optional pasted code to infer causes; the main risks are exposure of log contents and environment variables that may contain secrets, plus sending those details through AWS API calls.

Category levels, from 0 (none) to 3 (high)
Category	Level	Why
Code & shell execution	0 (none)	No native scripts or code execution are shipped with the skill; it only instructs the agent to make AWS CLI-style read operations such as `get-function-configuration` and `start-query`.
Network access	2 (moderate)	The procedure repeatedly calls remote AWS services (`aws lambda ...`, `aws cloudwatch ...`, `aws logs ...`) to fetch configuration, metrics, and log data, so function metadata and logs leave the local machine over the network.
Filesystem reach	0 (none)	The skill does not read, write, or delete local files outside the provided inputs, and it does not touch home dotfiles or system paths.
Secrets & credentials	2 (moderate)	It explicitly extracts Lambda `Environment variables` and queries full log messages, both of which can contain API keys, tokens, passwords, or other sensitive data.
Privilege & persistence	0 (none)	It does not request sudo, installs, services, shell changes, or other privilege-altering actions.
Instruction hijack surface	0 (none)	The markdown contains procedural instructions, but it does not tell the agent to ignore higher-level rules, skip confirmations, follow remote instructions, or hide anything.
Irreversible actions	0 (none)	The skill is diagnostic only; it produces a report and does not deploy, publish, pay, delete, or otherwise take irreversible actions.
Transparency	0 (none)	The shipped files are plain markdown with readable commands and no binaries, minified blobs, or downloaded/decoded runtime code.

Before installing

Use a least-privilege, read-only AWS role for the target account and region.
Confirm you are comfortable sharing CloudWatch logs, Lambda config, and any pasted `lambda_code` with the agent.
Check whether the function uses environment variables for secrets before running the analysis.
Verify CloudWatch log retention covers the time window you want to inspect.

Rated 2026-09-25 by an automated review of 2 files from the skill's repository.

Source

Repository: aws/agent-toolkit-for-aws (all skills from this repository)
Path: skills/specialized-skills/serverless-skills/debugging-lambda-timeouts/SKILL.md
Branch: main
Updated: 2026-09-19

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