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dynamodb_get_item

Read-onlyIdempotent

Retrieves a single DynamoDB item by table name and item ID from a local AWS emulator, helping assistants inspect stored data during testing and debugging.

Instructions

Read DynamoDB item

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "table": "<table>",
      "item_id": "<item_id>"
    },
    "name": "dynamodb_get_item"
  }
}

Input Schema

Name	Required	Description	Default
`table`	Yes
`item_id`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.4.0-beta.1Nov 13, 2026

TDQS

C2.4/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without the description. The description adds nothing beyond that - notably it does not say whether a missing item returns null, throws, or returns an empty result, which is the one behavior an agent most needs here.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three words with zero filler and the verb front-loaded, so structure is clean. It is under-specified rather than over-verbose, which caps the score since the brevity removes needed information rather than tightening it.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple (2 required params, no output schema, no nesting) and annotations carry the safety profile, so little is strictly required. Still, with 0% schema coverage the description should at minimum explain key format and miss behavior, and it does neither.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% for both parameters, so the schema supplies only names and types. The description does not clarify what "table" refers to (name vs ARN) or whether "item_id" is a single hash key or a composite key string, leaving the caller to guess the correct value shape.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose3/5

Does the description clearly state what the tool does and how it differs from similar tools?

"Read DynamoDB item" names a specific verb (Read) and resource (DynamoDB item), which is enough to distinguish it from dynamodb_put_item or dynamodb_delete_table. However, it is a bare phrase with no scope detail such as single-item key lookup, so purpose is only minimally established.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no guidance on when to use this tool versus alternatives, no mention of prerequisites (table must exist, item must exist), and no statement about what happens on a miss. The agent must infer everything from the name.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.