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aws-lambda-managed-instances

Evaluates, configures, and migrates workloads to AWS Lambda Managed Instances (LMI). Runs Lambda functions on EC2 instances in the user's account while AWS manages provisioning, patching, scaling, routing, and load balancing. Triggers when queries mention Lambda Managed Instances, LMI, capacity providers, multi-concurrent execution environments, EC2-backed Lambda, persistent Lambda instances, PerExecutionEnvironmentMaxConcurrency, CapacityProviderConfig, cold start elimination via dedicated instances, migrating standard Lambda to managed instances, or cost comparison between standard Lambda and LMI with Savings Plans or Reserved Instances. Also covers long-running and asynchronous workloads and the 90-minute (5400s) function timeout for asynchronous and event-source-mapping (SQS, Kinesis, DynamoDB Streams / ESM) invocations, including how to raise the function timeout up to 90 minutes / 5400s and the related duration limits.

72

Quality

88%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

SKILL.md
Quality
Evals
Security

Quality

Content

81%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is a well-structured, dense overview: a decision table, a disciplined one-file routing table, a sequenced migration workflow with validation checkpoints, and concrete commands and limits throughout, with detail correctly pushed to six real one-level-deep reference files. The main issues are repetition of the 90-minute timeout guidance across multiple sections and an orphaned bundled asset (assets/sqs-processor/template.yaml) that is never linked from any file.

Suggestions

Consolidate the 90-minute/5400s timeout guidance into a single authoritative section (Step 3 or the Limits table) and reference it from the other sections instead of restating it in the Quick Decision table, Step 1, and Best Practices.

Reference assets/sqs-processor/template.yaml from the body (e.g., in the Routing table and Files section as a ready-to-deploy SQS ESM example) so the bundled template is discoverable.

Inline one or two key commands in Step 5 (e.g., create-capacity-provider and function attachment) or link to the exact section of infrastructure-setup.md so the infrastructure step is executable without opening the whole reference file.

DimensionReasoningScore

Conciseness

The body is dense and fact-driven (decision table, routing table, limits table, bullet best practices) with no explanation of concepts Claude already knows, but the 90-minute/5400s timeout guidance is repeated across at least five sections (Quick Decision table, Step 1, Step 3, Best Practices, Limits) and Step 3 even restates "Uses the existing `Timeout` field" twice in one bullet. This fits 'efficient; minor instances of over-explanation that could be trimmed' rather than the lean anchor at 5, and is well above the noticeably-verbose anchor at 3.

4 / 5

Actionability

Guidance is highly concrete — exact CLI ("update-function-configuration --timeout 5400"), SAM/CFN syntax ("Timeout: 5400", "Architectures: [arm64]"), specific ratios (2:1/4:1/8:1), numeric caps per runtime, and a 5-step infrastructure checklist — but most full command sequences and code examples live in the reference files rather than inline. This is the 'mostly executable guidance; concrete code or commands with minor gaps' anchor rather than the fully copy-paste-ready coverage of common cases at 5.

4 / 5

Workflow Clarity

The six-step workflow (Assess → Cost comparison → Configure → Migrate → Infrastructure → Validate/Cutover) is clearly sequenced with explicit checkpoints: a required cost comparison before recommending, non-prod deployment first, CloudWatch monitoring criteria ("throttle rate > 1% and CPU > 80%"), and a gradual 10%→50%→100% traffic shift. The troubleshooting quick facts add error→cause→fix feedback loops, matching the anchor-5 pattern of explicit validation steps with error recovery.

5 / 5

Progressive Disclosure

The routing table maps each user need to exactly one reference file with the instruction "Read ONLY the single reference file that matches the user's task", all six referenced files exist, and the references are one level deep (verified: they contain only external links, no nested file references). However, the bundled asset assets/sqs-processor/template.yaml (a 98-line SAM template) is never referenced from SKILL.md or any reference file, leaving real bundle content undiscoverable — a minor organization gap that keeps this at 'good structure... minor organization gaps' rather than 5.

4 / 5

Total

17

/

20

Passed

Description

96%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description: it states concrete capabilities, explains the underlying mechanism, and provides an explicit and comprehensive trigger list covering both natural and technical phrasings. The only weaknesses are minor — some breadth in a few trigger phrases creates slight overlap risk with a generic AWS Lambda skill, and the 90-minute/5400s timeout detail is stated redundantly within the description itself.

DimensionReasoningScore

Specificity

"Evaluates, configures, and migrates workloads to AWS Lambda Managed Instances (LMI)" names three concrete actions, and the mechanism is spelled out concretely ("Runs Lambda functions on EC2 instances in the user's account while AWS manages provisioning, patching, scaling, routing, and load balancing"). Coverage spans the skill's full capability set with no padding-only abstractions, matching the comprehensive-actions anchor rather than the minor-gaps anchor at 4.

5 / 5

Completeness

Both questions are explicitly answered: what ("Evaluates, configures, and migrates workloads... Runs Lambda functions on EC2 instances...") and when ("Triggers when queries mention...") with a concrete trigger list. This mirrors the anchor-5 example structure (capability sentence plus explicit 'Use when'-style clause), not the 4 anchor where 'when' is only loosely specified.

5 / 5

Trigger Term Quality

Trigger terms are exhaustive and include natural synonyms and abbreviations users would actually say or paste: "Lambda Managed Instances, LMI, capacity providers, EC2-backed Lambda, persistent Lambda instances, PerExecutionEnvironmentMaxConcurrency, CapacityProviderConfig, cold start elimination via dedicated instances, migrating standard Lambda to managed instances, cost comparison... Savings Plans or Reserved Instances". Matches the comprehensive anchor including synonyms; the 4 anchor ('a few natural terms missing') does not fit since both colloquial and technical phrasings are present.

5 / 5

Distinctiveness Conflict Risk

The niche is clear and most triggers (LMI, CapacityProviderConfig, PerExecutionEnvironmentMaxConcurrency) are unambiguous, but broad phrases like "long-running and asynchronous workloads" and "migrating standard Lambda" could also plausibly route general Lambda/EC2 questions to this skill. This is the 'mostly distinct; minor overlap risk with closely related skills' anchor rather than 5, and clearly above 3 since the distinctive terminology dominates.

4 / 5

Total

19

/

20

Passed

Validation

93%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository
aws/agent-toolkit-for-aws
Reviewed

Table of Contents

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