DynamoDB MCP Server
DynamoDB MCP サーバー
Amazon DynamoDB リソースを管理するためのモデルコンテキストプロトコルサーバー。このサーバーは、テーブル管理、キャパシティ管理、データ操作のためのツールを提供します。
著者
イマン・カミヤビ ( ikmyb@icloud.com )
Related MCP server: AWS Athena MCP Server
特徴
テーブル管理
カスタマイズ可能な設定で新しい DynamoDB テーブルを作成する
既存のテーブルを一覧表示する
詳細なテーブル情報を取得する
テーブル設定を構成する
インデックス管理
グローバルセカンダリインデックス(GSI)の作成と管理
GSIの容量を更新
ローカルセカンダリインデックス(LSI)を作成する
キャパシティ管理
プロビジョニングされた読み取り/書き込み容量ユニットを更新する
テーブルスループット設定を管理する
データ操作
表内の項目を挿入または置換する
主キーでアイテムを取得する
特定のアイテム属性を更新する
条件付きでテーブルをクエリする
フィルターを使用してテーブルをスキャンする
注意: 誤ってデータが失われるのを防ぐため、削除操作はサポートされていません。
設定
依存関係をインストールします:
npm installAWS 認証情報を環境変数として設定します。
export AWS_ACCESS_KEY_ID="your_access_key"
export AWS_SECRET_ACCESS_KEY="your_secret_key"
export AWS_REGION="your_region"サーバーを構築します。
npm run buildサーバーを起動します。
npm startツール
テーブル作成
指定された設定で新しい DynamoDB テーブルを作成します。
パラメータ:
tableName: 作成するテーブルの名前partitionKey: パーティションキーの名前partitionKeyType: パーティションキーのタイプ (S=文字列、N=数値、B=バイナリ)sortKey: (オプション) ソートキーの名前sortKeyType: (オプション) ソートキーの種類readCapacity: プロビジョニングされた読み取り容量単位writeCapacity: プロビジョニングされた書き込み容量単位
例:
{
"tableName": "Users",
"partitionKey": "userId",
"partitionKeyType": "S",
"readCapacity": 5,
"writeCapacity": 5
}リストテーブル
アカウント内のすべての DynamoDB テーブルを一覧表示します。
パラメータ:
limit: (オプション) 返されるテーブルの最大数exclusiveStartTableName: (オプション) ページ区切りの開始テーブルの名前
例:
{
"limit": 10
}テーブルの説明
DynamoDB テーブルに関する詳細情報を取得します。
パラメータ:
tableName: 記述するテーブルの名前
例:
{
"tableName": "Users"
}作成_gsi
テーブルにグローバルセカンダリインデックスを作成します。
パラメータ:
tableName: テーブルの名前indexName: 新しいインデックスの名前partitionKey: インデックスのパーティションキーpartitionKeyType: パーティションキーの種類sortKey: (オプション) インデックスのソートキーsortKeyType: (オプション) ソートキーの種類projectionType: 投影の種類 (ALL、KEYS_ONLY、INCLUDE)nonKeyAttributes: (オプション) プロジェクトにキー以外の属性を追加するreadCapacity: プロビジョニングされた読み取り容量単位writeCapacity: プロビジョニングされた書き込み容量単位
例:
{
"tableName": "Users",
"indexName": "EmailIndex",
"partitionKey": "email",
"partitionKeyType": "S",
"projectionType": "ALL",
"readCapacity": 5,
"writeCapacity": 5
}更新_gsi
グローバルセカンダリインデックスのプロビジョニングされた容量を更新します。
パラメータ:
tableName: テーブルの名前indexName: 更新するインデックスの名前readCapacity: 新しい読み取り容量単位writeCapacity: 新しい書き込み容量単位
例:
{
"tableName": "Users",
"indexName": "EmailIndex",
"readCapacity": 10,
"writeCapacity": 10
}作成_lsi
テーブルにローカルセカンダリインデックスを作成します (テーブルの作成中に実行する必要があります)。
パラメータ:
tableName: テーブルの名前indexName: 新しいインデックスの名前partitionKey: テーブルのパーティションキーpartitionKeyType: パーティションキーの種類sortKey: インデックスのソートキーsortKeyType: ソートキーの種類projectionType: 投影の種類 (ALL、KEYS_ONLY、INCLUDE)nonKeyAttributes: (オプション) プロジェクトにキー以外の属性を追加するreadCapacity: (オプション) プロビジョニングされた読み取り容量単位writeCapacity: (オプション) プロビジョニングされた書き込み容量単位
例:
{
"tableName": "Users",
"indexName": "CreatedAtIndex",
"partitionKey": "userId",
"partitionKeyType": "S",
"sortKey": "createdAt",
"sortKeyType": "N",
"projectionType": "ALL"
}更新容量
テーブルのプロビジョニングされた容量を更新します。
パラメータ:
tableName: テーブルの名前readCapacity: 新しい読み取り容量単位writeCapacity: 新しい書き込み容量単位
例:
{
"tableName": "Users",
"readCapacity": 10,
"writeCapacity": 10
}アイテムを置く
テーブル内の項目を挿入または置き換えます。
パラメータ:
tableName: テーブルの名前item: テーブルに入れるアイテム(JSONオブジェクトとして)
例:
{
"tableName": "Users",
"item": {
"userId": "123",
"name": "John Doe",
"email": "john@example.com"
}
}アイテムを取得
主キーによってテーブルから項目を取得します。
パラメータ:
tableName: テーブルの名前key: 取得するアイテムの主キー
例:
{
"tableName": "Users",
"key": {
"userId": "123"
}
}アイテムの更新
テーブル内の項目の特定の属性を更新します。
パラメータ:
tableName: テーブルの名前key: 更新するアイテムの主キーupdateExpression: 更新式expressionAttributeNames: 属性名のマッピングexpressionAttributeValues: 更新式の値conditionExpression: (オプション) 更新の条件returnValues: (オプション) 返される値
例:
{
"tableName": "Users",
"key": {
"userId": "123"
},
"updateExpression": "SET #n = :name",
"expressionAttributeNames": {
"#n": "name"
},
"expressionAttributeValues": {
":name": "Jane Doe"
}
}クエリテーブル
キー条件とオプションのフィルターを使用してテーブルをクエリします。
パラメータ:
tableName: テーブルの名前keyConditionExpression: キー条件式expressionAttributeValues: キー条件式の値expressionAttributeNames: (オプション) 属性名のマッピングfilterExpression: (オプション) 結果のフィルター式limit: (オプション) 返されるアイテムの最大数
例:
{
"tableName": "Users",
"keyConditionExpression": "userId = :id",
"expressionAttributeValues": {
":id": "123"
}
}スキャンテーブル
オプションのフィルターを使用してテーブル全体をスキャンします。
パラメータ:
tableName: テーブルの名前filterExpression: (オプション) フィルター式expressionAttributeValues: (オプション) フィルタ式の値expressionAttributeNames: (オプション) 属性名のマッピングlimit: (オプション) 返されるアイテムの最大数
例:
{
"tableName": "Users",
"filterExpression": "age > :minAge",
"expressionAttributeValues": {
":minAge": 21
}
}サンプル質問
この DynamoDB MCP サーバーを使用するときに Claude に尋ねることができる質問の例を次に示します。
テーブル管理
「パーティションキー「productId」(文字列)とソートキー「timestamp」(数値)を持つ「Products」という新しい DynamoDB テーブルを作成します。」
「アカウント内のすべての DynamoDB テーブルを一覧表示する」
「Users テーブルの現在の構成は何ですか?」
「Usersテーブルのメールフィールドにグローバルセカンダリインデックスを追加する」
キャパシティ管理
「Usersテーブルの容量を20読み取り単位と15書き込み単位に更新します」
「Users テーブルの EmailIndex GSI 容量を拡大する」
「Orders テーブルに現在プロビジョニングされている容量はどれくらいですか?」
データ操作
「ID '123'、名前 'John Doe'、メールアドレス ' john@example.com ' の新しいユーザーを挿入します。」
「ID '123' のユーザーを取得する」
「ユーザー '123' のメールアドレスを ' john.doe@example.com ' に更新します」
「ユーザー '123' が行ったすべての注文を検索する」
「21歳以上のユーザーをすべてリストする」
「EmailIndex をクエリして、メールアドレス ' john@example.com ' を持つユーザーを検索します」
構成
AWS認証情報の設定
AWS マネジメントコンソールから AWS アクセスキー ID、シークレットアクセスキー、リージョンを取得します。
一時的な認証情報 (IAM ロールなど) を使用する場合は、セッション トークンも取得します。
これらの認証情報に DynamoDB 操作のための適切な権限があることを確認します。
Claude Desktopでの使用
これをclaude_desktop_config.jsonに追加します:
Docker(推奨)
{
"mcpServers": {
"dynamodb": {
"command": "docker",
"args": [ "run", "-i", "--rm", "-e", "AWS_ACCESS_KEY_ID", "-e", "AWS_SECRET_ACCESS_KEY", "-e", "AWS_REGION", "-e", "AWS_SESSION_TOKEN", "mcp/dynamodb-mcp-server" ],
"env": {
"AWS_ACCESS_KEY_ID": "your_access_key",
"AWS_SECRET_ACCESS_KEY": "your_secret_key",
"AWS_REGION": "your_region",
"AWS_SESSION_TOKEN": "your_session_token"
}
}
}
}建物
ドッカー:
docker build -t mcp/dynamodb-mcp-server -f Dockerfile .発達
自動リロード付きの開発モードで実行するには:
npm run devライセンス
このMCPサーバーはMITライセンスに基づいてライセンスされています。つまり、MITライセンスの条件に従って、ソフトウェアを自由に使用、改変、配布することができます。詳細については、プロジェクトリポジトリのLICENSEファイルをご覧ください。
Available Tools
12 toolscreate_gsiC
Creates a global secondary index on a table
| Name | Required | Description | Default |
|---|---|---|---|
| indexName | Yes | Name of the new index | |
| nonKeyAttributes | No | Non-key attributes to project (optional) | |
| partitionKey | Yes | Partition key for the index | |
| partitionKeyType | Yes | Type of partition key | |
| projectionType | Yes | Type of projection | |
| readCapacity | Yes | Provisioned read capacity units | |
| sortKey | No | Sort key for the index (optional) | |
| sortKeyType | No | Type of sort key (optional) | |
| tableName | Yes | Name of the table | |
| writeCapacity | Yes | Provisioned write capacity units |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure but provides minimal information. It states this is a creation operation but doesn't mention whether this requires specific permissions, whether it's a synchronous or asynchronous operation, what happens if the index already exists, or any rate limits or costs associated. For a complex database operation with 10 parameters, this is inadequate behavioral context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is extremely concise - a single sentence that directly states the tool's purpose without any unnecessary words. It's front-loaded with the core action and resource. Every word earns its place, making this an excellent example of efficient communication.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a complex database operation with 10 parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what a global secondary index is, when one would use it, what the operation returns, or how it differs from local secondary indexes. The agent would need to infer too much from the bare description and parameter names alone.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema description coverage is 100%, with all parameters well-documented in the input schema. The description adds no additional parameter information beyond what's already in the structured schema. According to the scoring rules, when schema coverage is high (>80%), the baseline is 3 even with no parameter information in the description.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('creates') and resource ('global secondary index on a table'), making the purpose immediately understandable. However, it doesn't differentiate this from the sibling tool 'create_lsi' (local secondary index), which would be important context for an AI agent choosing between similar tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance about when to use this tool versus alternatives. With sibling tools like 'create_lsi', 'create_table', and 'update_gsi' available, the agent receives no help in determining which tool is appropriate for different scenarios. There's no mention of prerequisites, constraints, or typical use cases.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
create_lsiC
Creates a local secondary index on a table (must be done during table creation)
| Name | Required | Description | Default |
|---|---|---|---|
| indexName | Yes | Name of the new index | |
| nonKeyAttributes | No | Non-key attributes to project (optional) | |
| partitionKey | Yes | Partition key for the table | |
| partitionKeyType | Yes | Type of partition key | |
| projectionType | Yes | Type of projection | |
| readCapacity | No | Provisioned read capacity units (optional, default: 5) | |
| sortKey | Yes | Sort key for the index | |
| sortKeyType | Yes | Type of sort key | |
| tableName | Yes | Name of the table | |
| writeCapacity | No | Provisioned write capacity units (optional, default: 5) |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden for behavioral disclosure. It states this is a creation operation (implying mutation) and mentions a timing constraint, but lacks details on permissions required, whether the operation is reversible, error conditions, or what happens to existing data. For a complex 10-parameter mutation tool, this is inadequate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that states the core purpose and key constraint without unnecessary words. It's appropriately sized and front-loaded with the essential information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a complex database index creation tool with 10 parameters, no annotations, and no output schema, the description is insufficient. It lacks information about what the tool returns, error handling, permissions needed, or how it interacts with sibling tools like 'create_table'. The timing constraint is helpful but doesn't compensate for other gaps.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, providing detailed documentation for all 10 parameters. The description adds no parameter-specific information beyond what's in the schema, so it meets the baseline of 3. However, it doesn't explain relationships between parameters (e.g., how projectionType relates to nonKeyAttributes).
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Creates a local secondary index') and the resource ('on a table'), with specific mention of the constraint 'must be done during table creation'. However, it doesn't explicitly differentiate from sibling 'create_gsi' (global secondary index), which is a closely related alternative.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides a critical constraint ('must be done during table creation'), which implies when to use it, but offers no explicit guidance on when to choose this tool over alternatives like 'create_gsi' or 'create_table'. No prerequisites or exclusions are mentioned beyond the timing constraint.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
create_tableC
Creates a new DynamoDB table with specified configuration
| Name | Required | Description | Default |
|---|---|---|---|
| partitionKey | Yes | Name of the partition key | |
| partitionKeyType | Yes | Type of partition key (S=String, N=Number, B=Binary) | |
| readCapacity | Yes | Provisioned read capacity units | |
| sortKey | No | Name of the sort key (optional) | |
| sortKeyType | No | Type of sort key (optional) | |
| tableName | Yes | Name of the table to create | |
| writeCapacity | Yes | Provisioned write capacity units |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'specified configuration' but fails to explain critical behaviors like whether this is a mutating operation, what permissions are required, if it's idempotent, or what happens on conflicts. For a creation tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that directly states the tool's function without unnecessary words. It's appropriately sized and front-loaded, making it easy to understand quickly with zero wasted content.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a complex table creation tool with 7 parameters, no annotations, and no output schema, the description is inadequate. It doesn't explain what the tool returns, error conditions, or behavioral nuances, leaving too much unspecified for proper agent usage despite the comprehensive parameter schema.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema description coverage is 100%, so the schema already documents all parameters thoroughly. The description adds no additional parameter semantics beyond implying configuration is needed, which doesn't provide value beyond what the schema offers. This meets the baseline for high schema coverage.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Creates') and resource ('new DynamoDB table'), making the purpose evident. However, it doesn't differentiate from sibling tools like 'create_gsi' or 'create_lsi' that also create DynamoDB structures, leaving some ambiguity about when to choose this specific tool.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'create_gsi' or 'create_lsi', nor does it mention prerequisites or context for table creation. It simply states what it does without indicating appropriate scenarios or exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
describe_tableC
Gets detailed information about a DynamoDB table
| Name | Required | Description | Default |
|---|---|---|---|
| tableName | Yes | Name of the table to describe |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It states this is a read operation ('Gets'), implying it's non-destructive, but doesn't mention authentication requirements, rate limits, error conditions, or what 'detailed information' includes (e.g., schema, throughput, status). For a tool with zero annotation coverage, this leaves significant behavioral gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence with zero wasted words. It's front-loaded with the core purpose and appropriately sized for a simple tool. Every word earns its place without being overly terse or verbose.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the lack of annotations and output schema, the description is incomplete. It doesn't explain what 'detailed information' entails (e.g., table properties, indexes, status), which is critical for a metadata tool. With no behavioral context and minimal parameter guidance, it fails to provide enough information for effective agent use despite the simple schema.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, with the single parameter 'tableName' clearly documented in the schema. The description adds no additional parameter semantics beyond what's in the schema—it doesn't clarify format constraints, naming conventions, or examples. The baseline score of 3 reflects adequate coverage when the schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the verb ('Gets') and resource ('detailed information about a DynamoDB table'), making the purpose understandable. It distinguishes this from siblings like 'list_tables' (which lists table names) and 'create_table' (which creates tables), but doesn't explicitly differentiate from other read operations like 'get_item' or 'query_table' beyond the resource scope.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose 'describe_table' over 'list_tables' for metadata, or how it differs from 'get_item' or 'query_table' for data retrieval. There are no prerequisites, exclusions, or contextual usage hints provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_itemC
Retrieves an item from a table by its primary key
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | Primary key of the item to retrieve | |
| tableName | Yes | Name of the table |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool retrieves an item, implying a read-only operation, but doesn't specify whether it returns null for missing keys, requires specific permissions, has rate limits, or details the return format (e.g., JSON object). For a read tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that front-loads the core action ('retrieves an item') and includes essential details ('from a table by its primary key'). There is no wasted text, making it highly concise and well-structured for quick understanding.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the complexity of database operations, no annotations, and no output schema, the description is incomplete. It doesn't explain what happens if the key doesn't exist, the return format, error conditions, or how it differs from sibling tools like 'query_table'. For a tool with 2 parameters and rich sibling context, more detail is needed to fully guide an agent.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, with clear descriptions for both parameters ('key' as primary key and 'tableName' as table name). The description adds minimal value beyond the schema by mentioning 'by its primary key,' which reinforces the schema's 'key' parameter but doesn't provide additional syntax or format details. Baseline 3 is appropriate when the schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool's purpose with a specific verb ('retrieves') and resource ('item from a table'), specifying it uses the primary key. It distinguishes from siblings like 'put_item' (create) or 'update_item' (modify) by focusing on retrieval, though it doesn't explicitly contrast with 'query_table' or 'scan_table' for alternative lookup methods.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'query_table' or 'scan_table', which also retrieve items but with different methods (e.g., by query conditions or full scans). It lacks context on prerequisites, such as needing an existing table, or exclusions, like not supporting secondary indexes.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_tablesC
Lists all DynamoDB tables in the account
| Name | Required | Description | Default |
|---|---|---|---|
| exclusiveStartTableName | No | Name of the table to start from for pagination (optional) | |
| limit | No | Maximum number of tables to return (optional) |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden but only states the basic function. It doesn't disclose behavioral traits like pagination behavior (implied by parameters but not explained), rate limits, authentication requirements, or what the output format looks like. This leaves significant gaps for an agent to understand how the tool behaves.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded and wastes no space, making it easy for an agent to parse quickly.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's moderate complexity (listing resources with pagination), lack of annotations, and no output schema, the description is incomplete. It fails to cover key aspects like output format, error handling, or integration with sibling tools, leaving the agent with insufficient context for reliable use.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema has 100% description coverage, clearly documenting both optional parameters for pagination and limits. The description adds no additional parameter semantics beyond what the schema provides, so it meets the baseline of 3 for adequate but not enhanced coverage.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Lists') and resource ('all DynamoDB tables in the account'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'describe_table' or 'scan_table', which prevents a perfect score.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'describe_table' for detailed table information or 'scan_table' for data retrieval. It lacks context about prerequisites, such as requiring AWS permissions, or when listing tables is appropriate in a workflow.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
put_itemC
Inserts or replaces an item in a table
| Name | Required | Description | Default |
|---|---|---|---|
| item | Yes | Item to put into the table | |
| tableName | Yes | Name of the table |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool 'Inserts or replaces an item', implying a mutation operation, but fails to detail critical aspects like permissions needed, whether the operation is idempotent, error handling, or side effects. This is a significant gap for a mutation tool with zero annotation coverage.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that directly states the tool's function without unnecessary words. It is appropriately sized and front-loaded, making it easy to understand at a glance.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a mutation tool with no annotations, no output schema, and incomplete behavioral details, the description is inadequate. It does not explain return values, error conditions, or how 'inserts or replaces' differs from other operations, leaving the agent with insufficient context for reliable use.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, with both parameters ('item' and 'tableName') documented in the schema. The description adds no additional meaning beyond what the schema provides, such as format details or constraints. Given the high schema coverage, a baseline score of 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Inserts or replaces') and the resource ('an item in a table'), making the purpose understandable. However, it does not explicitly differentiate this tool from sibling tools like 'update_item' or 'create_table', which might handle similar operations, so it misses the highest score.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives such as 'update_item' or 'create_table'. It lacks context about prerequisites, exclusions, or specific scenarios, leaving the agent to infer usage based on the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
query_tableC
Queries a table using key conditions and optional filters
| Name | Required | Description | Default |
|---|---|---|---|
| expressionAttributeNames | No | Attribute name mappings | |
| expressionAttributeValues | Yes | Values for the key condition expression | |
| filterExpression | No | Filter expression for results | |
| keyConditionExpression | Yes | Key condition expression | |
| limit | No | Maximum number of items to return | |
| tableName | Yes | Name of the table |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden but offers minimal behavioral context. It doesn't disclose whether this is a read-only operation, what permissions are required, how results are returned (pagination, format), error conditions, or performance characteristics. The mention of 'optional filters' hints at filtering capability but lacks detail.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that communicates the core functionality without unnecessary words. It's front-loaded with the main action and resource, making it immediately understandable.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a database query tool with 6 parameters, no annotations, and no output schema, the description is inadequate. It doesn't explain what the tool returns, error handling, authentication requirements, or how it differs from similar operations. The context signals indicate significant complexity that isn't addressed.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents all 6 parameters thoroughly. The description adds marginal value by mentioning 'key conditions' (mapping to keyConditionExpression) and 'optional filters' (mapping to filterExpression), but doesn't provide additional semantic context beyond what's in the schema descriptions.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Queries') and resource ('a table'), specifying it uses 'key conditions and optional filters'. This distinguishes it from siblings like 'scan_table' (full table scan) and 'get_item' (single item retrieval), though it doesn't explicitly name these alternatives.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'scan_table' or 'get_item'. It mentions 'key conditions' which implies it's for indexed queries, but doesn't state this explicitly or provide any exclusion criteria or prerequisites.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
scan_tableC
Scans an entire table with optional filters
| Name | Required | Description | Default |
|---|---|---|---|
| expressionAttributeNames | No | Attribute name mappings | |
| expressionAttributeValues | No | Values for the filter expression | |
| filterExpression | No | Filter expression | |
| limit | No | Maximum number of items to return | |
| tableName | Yes | Name of the table |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries full burden. It mentions scanning with filters but doesn't disclose critical behavioral traits: whether this is a read-only operation, performance implications of scanning entire tables, pagination behavior, error conditions, or authentication requirements. For a table scanning operation with no annotation coverage, this leaves significant gaps in understanding tool behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is extremely concise - a single sentence that communicates the core functionality efficiently. Every word earns its place: 'Scans' (action), 'entire table' (resource and scope), 'with optional filters' (key capability). No wasted words or unnecessary elaboration.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given this is a database scanning operation with 5 parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what scanning returns, performance implications, error handling, or how this differs from query operations. For a potentially resource-intensive table operation, more context about behavior and limitations is needed.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents all 5 parameters thoroughly. The description adds minimal value beyond the schema - it mentions 'optional filters' which aligns with filterExpression, expressionAttributeNames, and expressionAttributeValues parameters, but doesn't provide additional context about filter syntax, performance tradeoffs, or relationship between parameters. Baseline 3 is appropriate when schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Scans an entire table with optional filters' clearly states the verb ('scans') and resource ('table'), but is somewhat vague about scope ('entire' vs 'filtered') and doesn't distinguish from sibling tools like 'query_table' or 'get_item'. It provides basic purpose but lacks specificity about what scanning entails compared to alternatives.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance is provided about when to use this tool versus alternatives like 'query_table' or 'get_item'. The description mentions 'optional filters' but doesn't explain when filtering is appropriate or what distinguishes scanning from querying. Without usage context, the agent must infer based on tool names alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
update_capacityC
Updates the provisioned capacity of a table
| Name | Required | Description | Default |
|---|---|---|---|
| readCapacity | Yes | New read capacity units | |
| tableName | Yes | Name of the table | |
| writeCapacity | Yes | New write capacity units |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It states 'Updates' implies a mutation, but doesn't disclose critical traits like required permissions, whether changes are reversible, potential costs or rate limits, or what happens if invalid capacity values are provided. This is a significant gap for a mutation tool with zero annotation coverage.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence with zero waste, front-loaded with the core action. It's appropriately sized for the tool's complexity, making it easy to parse quickly without unnecessary elaboration.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's complexity as a mutation operation with no annotations and no output schema, the description is incomplete. It lacks information on behavioral aspects (e.g., side effects, error handling) and doesn't explain what the tool returns, leaving the agent with insufficient context for reliable use.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The description adds no meaning beyond what the input schema provides, as schema description coverage is 100% with clear parameter descriptions. The baseline score of 3 is appropriate because the schema does the heavy lifting, but the description doesn't compensate with additional context like units of capacity or constraints on values.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the verb ('Updates') and resource ('provisioned capacity of a table'), making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'update_gsi' or 'update_item', which might also involve updates to table-related resources, leaving some ambiguity about scope.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., the table must exist), exclusions (e.g., cannot be used with certain table types), or related tools like 'create_table' or 'describe_table' for context, leaving the agent to infer usage from the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
update_gsiC
Updates the provisioned capacity of a global secondary index
| Name | Required | Description | Default |
|---|---|---|---|
| indexName | Yes | Name of the index to update | |
| readCapacity | Yes | New read capacity units | |
| tableName | Yes | Name of the table | |
| writeCapacity | Yes | New write capacity units |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden for behavioral disclosure. It states this is an update operation but doesn't mention whether this requires specific permissions, whether it's a destructive change, what happens to existing capacity settings, rate limits, or what the response looks like. For a capacity management tool with zero annotation coverage, this leaves significant behavioral gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that gets straight to the point with zero wasted words. It's appropriately sized for what it communicates and is perfectly front-loaded with the essential information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a capacity update tool with no annotations and no output schema, the description is insufficient. It doesn't explain what 'provisioned capacity' means in practical terms, what units are used, whether changes are immediate or gradual, what validation occurs, or what happens on failure. The context signals show this is a 4-parameter mutation tool that needs more behavioral context.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema description coverage is 100%, so all parameters are documented in the input schema. The description doesn't add any additional parameter context beyond what's already in the schema properties. It mentions 'provisioned capacity' which aligns with the readCapacity and writeCapacity parameters, but provides no extra semantic value.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the action ('Updates') and the resource ('provisioned capacity of a global secondary index'), making the purpose immediately understandable. It doesn't explicitly differentiate from siblings like 'update_capacity' or 'update_item', but the specificity of 'global secondary index' provides some implicit distinction.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'update_capacity' or 'create_gsi'. It doesn't mention prerequisites, dependencies, or scenarios where this operation is appropriate versus other update operations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
update_itemC
Updates specific attributes of an item in a table
| Name | Required | Description | Default |
|---|---|---|---|
| conditionExpression | No | Condition for update (optional) | |
| expressionAttributeNames | Yes | Attribute name mappings | |
| expressionAttributeValues | Yes | Values for the update expression | |
| key | Yes | Primary key of the item to update | |
| returnValues | No | What values to return | |
| tableName | Yes | Name of the table | |
| updateExpression | Yes | Update expression (e.g., 'SET #n = :name') |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'Updates' which implies mutation, but fails to describe critical behaviors: whether this is idempotent, what happens if the item doesn't exist, what permissions are required, whether changes are reversible, or what the response format looks like. For a mutation tool with zero annotation coverage, this is a significant gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, efficient sentence that gets straight to the point without any wasted words. It's appropriately sized for the tool's complexity and front-loads the core functionality.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a mutation tool with 7 parameters (including complex nested objects), no annotations, and no output schema, the description is inadequate. It doesn't explain the return values, error conditions, or the behavioral implications of the update operation. The agent would need to rely heavily on the schema alone, missing important contextual information about how this tool behaves in practice.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema description coverage is 100%, so all parameters are documented in the schema itself. The description adds minimal value beyond what's in the schema - it mentions 'specific attributes' which aligns with the updateExpression parameter, but doesn't provide additional context about parameter relationships or usage patterns. The baseline of 3 is appropriate when the schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the verb ('Updates') and resource ('specific attributes of an item in a table'), making the purpose understandable. However, it doesn't explicitly differentiate this from sibling tools like 'put_item' (which might create/replace items) or 'update_capacity' (which modifies table capacity), leaving some ambiguity about when to choose this specific update tool.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives like 'put_item' (for full item replacement) or 'update_capacity' (for table-level changes). It lacks context about prerequisites (e.g., requires existing item), exclusions, or typical scenarios, leaving the agent to infer usage from the tool name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
12 tool updates
v1.0.0- First observed
create_gsi - First observed
create_lsi - First observed
create_table - First observed
describe_table - First observed
get_item - First observed
list_tables - First observed
put_item - First observed
query_table - First observed
scan_table - First observed
update_capacity - First observed
update_gsi - First observed
update_item
TDQS
Scored across 12 tools
Each tool has a clearly distinct purpose targeting specific DynamoDB operations with no overlap. For example, create_table vs. describe_table vs. update_item are all unambiguous in their functions, and even similar-sounding tools like query_table and scan_table are clearly differentiated in their descriptions.
All tools follow a consistent verb_noun pattern with snake_case throughout, such as create_table, describe_table, and update_item. The naming is predictable and readable, making it easy for agents to understand the action and target resource.
With 12 tools, this server is well-scoped for DynamoDB operations, covering core CRUD, indexing, capacity management, and table lifecycle. Each tool earns its place without being overwhelming or insufficient for the domain.
The tool set provides strong coverage of DynamoDB's key operations, including table management, item CRUD, indexing, and capacity updates. A minor gap is the lack of tools for deleting tables or indexes, which could limit full lifecycle management, but core workflows are well-supported.
Maintenance
Related MCP Connectors
Design domain models and generate deterministic multi-stack code, driven by your coding agent.
Hosted MCP server for AI-driven data ops. Create apps, manage schemas, and CRUD structured data.
Public tools to understand Dynamik, discover datasets, and connect account-scoped capabilities.
Create AgentUI data apps: define tables, read and write records, and run programs on your data.
1
Related MCP Servers
- AlicenseNot gradedqualityDmaintenanceEnables comprehensive SQLite database operations including CRUD operations, schema management, and meta commands across multiple database files through the Model Context Protocol.25 npm2MIT
- AlicenseNot gradedqualityBmaintenanceEnables execution of SQL queries against AWS Athena databases with schema discovery, query status management, and result retrieval through a standardized Model Context Protocol interface.123 PyPI23MIT
- FlicenseAqualityDmaintenanceEnables interaction with Grist documents, workspaces, and records via the Model Context Protocol. It supports comprehensive operations including SQL querying, schema management, and record CRUD functionality.11204 npm4-
- FlicenseNot gradedqualityDmaintenanceEnables interaction with AWS services (EC2, S3, Lambda, DynamoDB, etc.) through the Model Context Protocol, allowing natural language management of cloud resources.2-