opensheet
OpenSheet
データベースなしのデータベースUI。
テーブルはディスク上のプレーンな .jsonl ファイルです。1つのセルを編集すると、git diff には1行だけが表示されます。
OpenSheetを閉じても、jq、DuckDB、Excel、pandas、そしてAIエージェントはすべてを読み取ることができます。
これは何か
スプレッドシート型データベースツールは、行をどこかに保存する必要があります。一般的な答えは、自分で起動しなければならないデータベース、アプリに同梱されるストレージエンジン、またはアプリ独自の形式の単一バイナリファイルです。どれも機能します。しかし、どれもツールがあなたとデータの間に立ちはだかることを意味します。
OpenSheetの信頼できる情報源は、あなたがすでに読み方を知っているテキストファイルです。1つのフォルダがライブラリ、その中の各 .jsonl がテーブル、1行がレコードです。データベースも、アカウントも、サーバーも、同期もありません。OpenSheetを削除しても、データは1ミリも動きません。
$ cat my-library/campaigns.jsonl
{"id":"KS-001","project":"Modular Mechanical Keyboard","raised_usd":412870,"rating":5}
{"id":"KS-002","project":"Solar Camp Lantern","raised_usd":88250,"rating":4}
$ jq -r 'select(.rating == 5) | .project' my-library/campaigns.jsonl
Modular Mechanical Keyboardこれがストレージ形式のすべてです。スプレッドシートUIは、それを包み込むラッパーではなく、それに対するビューです。
Related MCP server: jsony-mcp
クイックスタート
Python 3.9+ が必要です。pip installも、Dockerも、ビルドステップも不要です。
git clone https://github.com/newgepard/opensheet
cd opensheet
PYTHONPATH=src python3 -m opensheet ~/my-library/ブラウザで http://127.0.0.1:<空きポート> が開きます。.jsonl ファイルのフォルダ、単一の .jsonl ファイル、またはゼロから始めるための空のフォルダを指定します。
macOSデスクトップアプリ — 860 KBのネイティブシェル(Swift + WKWebView、システムのWebKitを使用):
bash shell/build.sh
open shell/build/OpenSheet.app忠実性の約束
これが他のすべての基盤であり、断言ではなくテストされています。
1. 触っていない行はバイト単位でそのまま書き戻されます。 10,000行のテーブルで1つのセルを編集すると、git diff には正確に1行の変更だけが表示されます。触っていない行が再シリアライズされることはありません — 並べ替えも、再フォーマットも、再エスケープもされません。
2. 非ASCIIテキストは決してエスケープされません。 {"名前":"甲"} はそのまま維持されます。json.dumps がデフォルトで行い、JSONパーサー以外のすべてのツールでファイルを読めなくする {"\u540d\u524d":"\u7532"} に変わることは決してありません。
3. スパースファイルはスパースのままです。 行にキーがない場合、OpenSheetはそのキーを勝手に作りません。50,000行の既存テーブルにフィールドを追加しても、書き換えられる行はゼロです。
元に戻すはスナップショットロールバックではなく逆コマンドとして実装されており、特に約束1がそれを生き残るためです: セルを編集し、⌘Z を押し、保存 — git diff は空です。スナップショット復元の実装は、画面上では正しく見えても、触れたすべての行を静かに再シリアライズすることになります。

これを支えているのは: フィンガープリントチェックがOpenSheetの背後で行われた変更の上書きを拒否し、書き込みは一時ファイルと os.replace() を経由し、すべての保存でオープン時スナップショットと並んで .bak が保持されます。
機能
データはあなたが所有するファイル — プレーンな
.jsonlで、jq、DuckDB、pandas、Excel、gitで読み取り可能すべてを元に戻せる —
⌘Z/⇧⌘Z; バッチ削除は単一の元に戻すステップにまとまる13のフィールドタイプ — テキスト、数値、セレクト、マルチセレクト、日付、チェックボックス、URL、添付ファイル、数式、テーブル間ルックアップ、作成/更新時刻、自動番号。数値は保存された値を変更せずにプログレスバー、通貨、評価、パーセンテージとして表示可能
4つのビュータイプ — グリッド、カンバン、ギャラリー、さらにビューごとのフィルター、ソート、グループ化、統計、行の高さ、列の固定、列の順序
10,000行でもスムーズ — 仮想スクロール; 7.5 MBのテーブルの読み込み57 ms、保存59 msと測定
インポートとエクスポート — CSV、XLSX、JSON、SQLite、
.gristからのインポート; CSV、XLSX、JSON、JSONL、Markdown、Parquetへのエクスポート添付ファイルはローカルに留まる — ファイルは
<library>/assets/に置かれ、セルは相対パスを保持し、どこにもアップロードされない
エージェントのために作られ、AIで飾られていない
スプレッドシートにAIボタンを追加するのは機能です。エージェントがアダプターなしで読み書きできるストレージ形式を選ぶのはアーキテクチャです。OpenSheetは後者を行い、他のすべてはそこから導かれます: ファイルは行指向なので追記は >>、形式はテキストなので grep が機能し、ライターは単一なのでバイト忠実性が並行アクセスでも維持されます。
MCPサーバーはHTTPサーバーと同じプロセスで実行され、1つの Store インスタンスを共有します:
{
"mcpServers": {
"opensheet": {
"command": "python3",
"args": ["-m", "opensheet", "/path/to/libraries", "--mcp", "--mcp-root", "/path/to/libraries"],
"env": { "PYTHONPATH": "/path/to/opensheet/src" }
}
}
}ツール: list_libraries、list_tables、get_schema、query、upsert_rows。
upsert_rows はレシート — inserted / updated / unchanged のカウントと各プライマリキー — を返し、dry_run をサポートします。ディスク上にすでにあるものと同一の行は unchanged としてカウントされ、ファイルは触られません。
同じプロセスであることは実装の詳細ではありません。 バイト忠実性はプロセス内の状態に依存します: 各行がどのバイトとして到着したか。それぞれが独自のコピーを持つ2つのプロセスは、互いの書き込みを「変更」と結論し、次の保存でファイル全体を再シリアライズすることになります。2番目のプロセスはロックファイルを検出して最初のプロセスに転送するため、常に正確に1つのライターが存在します。
エージェントはOpenSheetをスキップしてファイルに直接追記することもできます。その際に忠実性を維持するルールは直接書き込みガイドに文書化されています。
アーキテクチャ
graph TD
A["my-library/"] --> B["campaigns.jsonl<br/>source of truth"]
A --> C["suppliers.jsonl"]
A --> D[".opensheet/<br/>schema · views · links"]
B --> E["store.py<br/>row passthrough · atomic write"]
C --> E
E --> F["single process"]
F --> G["HTTP + browser UI"]
F --> H["MCP over stdio"]
G --> I["native macOS shell"].opensheet/ にはフィールドタイプ、列幅、ビュー定義、テーブル間リンクが保持されます。これを削除するとフォーマットは失われますが、データは失われません — フィールドタイプは推論にフォールバックします。
なぜ小さく保たれるのか
バックエンドはPython標準ライブラリのみです。フロントエンドはプレーンなJavaScript — フレームワークもビルドステップもありません。macOSシェルはバンドルされたブラウザではなく、システムWebKit上の184 KBのSwiftです。
DuckDBはオプションで読み取り専用であり、SQLパネルとParquetエクスポートを提供します。フィルタリング、ソート、グループ化には決して参加せず、書き込みも決して行いません。すべての書き込みは store.py を経由します。
ネットワークなし、構造的に
テレメトリも、更新チェックも、CDNアセットも、オンラインデモもありません。ブラウザは同一オリジンの /api/* パスのみをリクエストし、サーバーはIPv4ループバックのみにバインドし、デスクトップシェルは独自のTCP接続をゼロ保持します。tests/test_offline.py がこれらすべてを強制します。
検証
bash tests/opensheet-全量验收-20260815.sh329テスト: JavaScriptユニット188、Python 83、ブラウザE2E 42(Playwright)、忠実性ラウンドトリップ8、ライブラリラウンドトリップ8。 忠実性テストはフィールド単位ではなくバイト単位でファイルを比較します — 値だけをチェックするテストは、約束1が静かに破られていても合格してしまうでしょう。
ブラウザテストには、PlaywrightのChromium用に web/ 内で npm install が必要です。
OpenSheetがやらないこと
コメント、権限、リアルタイムコラボレーション、自動化、ホスト型バージョン、オンラインデモ。 これらはそれぞれアカウントシステムか公開アドレスを必要とし、最初の設計制約であるデータがマシンから出ることはないという原則に矛盾します。
これは意図的な境界であり、ロードマップの欠落ではありません。
ステータス
動作しており毎日使用されていますが、試す前に知っておくべき2つの粗い部分があります:
UIは現在中国語のみです。 コード、コメント、インターフェース文字列はすべて中国語です。英語のローカライゼーションはまだ行われていません。
デスクトップシェルはmacOSのみです。 Web版はPythonが動作するどこでも動作します。
コントリビューション
IssueとPRは歓迎します。ストレージ層に触れる前に知っておくべきことが2つあります:
store.pyの行パススルーロジックこそが製品です。それを変更するということは、忠実性テストをグリーンに保つことを意味し、それらのテストはフィールドではなくバイトを比較します。コードコメントは現在中国語です。翻訳の助けは大歓迎です。
ライセンス
MIT — LICENSE を参照してください。
Available Tools
5 toolsget_schemaC
读取表字段 schema
| Name | Required | Description | Default |
|---|---|---|---|
| table | Yes | ||
| library | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The verb '读取' indicates a read-only, non-mutating operation, which is useful since siblings include upsert_rows. However, with no annotations, the description carries the full burden and does not disclose return format, permissions, or potential errors, so transparency is only partial.
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 short sentence with no filler, and the core action is front-loaded. It is concise, though slightly under-specified, which is more a completeness issue than a structure problem.
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?
With no annotations, no output schema, and 0% parameter description coverage, the definition leaves the agent without enough context about how to supply library/table values or what the returned schema will look like. Sibling names hint at a workflow, but the description itself does not establish it.
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 0%: the input schema only gives parameter names and types. The description mentions '表字段' (table fields) but leaves 'library' unexplained, and provides no value formats or how to obtain valid inputs, so it does not compensate for the missing 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 '读取表字段 schema' clearly states a read operation on a table's field schema, with a specific resource and scope. It is distinguishable from siblings like query (data retrieval) and list_tables (table enumeration), though it does not name them explicitly.
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?
There is no guidance on when to use this tool instead of list_tables or query, and no exclusions or prerequisite steps are mentioned. The intended workflow (first list libraries/tables, then fetch schema) is only inferable from sibling names, not stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_librariesA
列出根目录内的 OpenSheet 库
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description carries the full burden. It clearly indicates a read-only listing operation scoped to the root directory, but it does not disclose details such as pagination, sorting, whether nested libraries are included, or what the response shape is. For a no-parameter list operation, this is adequate but minimal.
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 concise sentence that immediately communicates the action and scope. There is no filler or redundant 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?
Given the zero-parameter schema and no output schema, the description is nearly sufficient: it names the action, resource, and scope. Minor gaps include no statement about non-recursive behavior or return format, but the tool is simple enough that these are not critical.
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 tool has zero parameters, so there is no schema burden to compensate for. The description appropriately focuses on output scope rather than parameter details, matching the baseline for parameterless tools.
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 uses a specific verb ('列出') and a specific resource ('根目录内的 OpenSheet 库'), clearly distinguishing this from siblings like list_tables, which lists tables rather than libraries. The scope 'root directory' adds useful precision.
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 states what the tool does but gives no guidance on when to choose it over alternatives, nor any exclusions or prerequisites. An agent must infer from sibling names and the description that this is the tool for listing libraries, not tables or schemas.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_tablesB
列出库里的 JSONL 表
| Name | Required | Description | Default |
|---|---|---|---|
| library | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description bears the full burden. The verb '列出' implies a read-only listing operation, but the description does not disclose output format, pagination, error behavior, or whether any library validation occurs. It is minimally transparent but not richly so.
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 short sentence with no redundant words. The operation and scope are front-loaded, making it easy 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?
For a tool with one required parameter and no output schema, the description gives only minimal context. It does not explain what a 'JSONL 表' is exactly, what the agent should do with the returned list, or how to obtain a valid library value. The ambiguity around 'JSONL' and library selection leaves meaningful 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 0%, so the description must compensate. The phrase '库里的' clarifies that the 'library' parameter identifies which library's tables are listed. However, it does not explain valid library identifier formats, whether values come from list_libraries, or how missing/invalid libraries are handled.
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 operation ('列出' / list) and the resource ('JSONL 表' / tables) scoped to a library. It is easily distinguished from siblings like list_libraries, though it does not explicitly name the sibling it differs from.
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 given on when to use this tool versus siblings such as get_schema, query, or list_libraries. The description only states what it does, not when it should be chosen or what prerequisite steps (like selecting a library) are needed.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
queryB
用只读 DuckDB SQL 查询表
| Name | Required | Description | Default |
|---|---|---|---|
| sql | Yes | ||
| table | Yes | ||
| library | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It does disclose the critical read-only trait, which is essential for an agent to know this tool will not mutate data. It says nothing about return shape, SQL restrictions beyond read-only, error behavior, or permission requirements, so transparency is partial rather than complete.
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 concise sentence with no filler. The key behavioral qualifier 'read-only' is front-loaded, and every word contributes meaning.
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 tool with three required parameters, zero schema descriptions, and no annotations, the description is too sparse. An agent still lacks clarity about the 'library' parameter, whether results are returned in a specific format, and what SQL constructs are allowed beyond the read-only restriction.
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 0% and the description adds little to parameter meaning beyond what the parameter names already imply. 'sql' and 'table' are self-explanatory, but 'library' remains ambiguous and there is no guidance on how the three parameters relate or what format the SQL should follow.
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 states a specific action—querying tables via DuckDB SQL—and explicitly marks it as read-only, which distinguishes it from upsert_rows. It does not explicitly name sibling tools or contrast its scope with list/get_schema tools, so it is clear but not maximally differentiated.
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 read-only qualifier implies this tool is for SELECT-style data retrieval and not for modifications, giving some usage direction. However, it does not explicitly state when to choose this over list_libraries, list_tables, or get_schema, leaving the routing mostly to inference from the tool name and siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
upsert_rowsA
按指定主键批量新增或更新,走与 HTTP 相同的 Store 并发保护。返回回执:inserted / updated / unchanged 计数与各自的主键值列表。dry_run=true 只算回执不落盘。
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | ||
| rows | Yes | ||
| table | Yes | ||
| dry_run | No | 只返回将发生的变更,不写文件 | |
| library | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full responsibility for behavior disclosure, and it delivers: it mentions Store concurrency protection, the exact receipt format (inserted/updated/unchanged counts and key lists), and the no-persistence behavior of dry_run=true. It does not cover error or validation behavior, but the most decision-relevant side effects are explicit.
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?
Three compact sentences cover the core operation, concurrency protection, return receipt, and dry-run behavior. The most essential verb and scope are front-loaded with no redundant filler.
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?
The description compensates for the missing output schema by stating the receipt shape, and it covers the operation's key nuances. It lacks row-structure details and failure semantics, which would help for a 5-parameter mutation tool, but it is sufficiently complete for a competent agent to call the tool correctly in the common case.
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 coverage is only 20%, with only dry_run documented. The description adds meaning by identifying key as the primary key, rows as the batch payload, and clarifying dry_run semantics. However, it does not explain how rows should encode the key or what values library/table expect, leaving part of parameter construction to inference.
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 opens with '按指定主键批量新增或更新', a specific verb (upsert) and a clear resource (rows keyed by primary key). This immediately distinguishes it from the read-only and metadata sibling tools like query and list_tables, so an agent can tell what it does without needing more context.
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 conveys that the tool is for batch insert-or-update operations by primary key and even highlights the dry_run inspection mode. However, it never explicitly contrasts it with alternatives such as query for reads or states when not to use it. The usage context is clear but the tool-selection guidance is only implied, not spelled out.
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.
5 tool updates
v0.1.0- First observed
get_schema - First observed
list_libraries - First observed
list_tables - First observed
query - First observed
upsert_rows
TDQS
Scored across 5 tools
Each tool maps to a distinct action and resource level: libraries, tables, schema, query, and upsert. There is no meaningful overlap, and the descriptions reinforce the boundaries clearly.
Most tool names follow a clear verb_noun snake_case pattern: list_libraries, list_tables, get_schema, upsert_rows. The single-word 'query' is a minor deviation, but the overall naming style remains uniform and predictable.
Five tools is well-scoped for an OpenSheet data access server. Each tool covers a necessary step in the workflow without redundancy or bloat.
The set covers the core workflow well: discovering libraries, listing tables, inspecting schema, querying data, and upserting rows. The main gap is the lack of any delete or schema-mutation capability, but that may be intentionally out of scope for this server.
Maintenance
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