Umi-OCR MCP Server
This server exposes Umi-OCR's local OCR capabilities to AI agents over MCP, enabling text extraction from images, directories, and PDFs with automatic service management and workflow prompts.
Check OCR service status:
quick_ocr_statusfor a minimal online/offline check,check_ocr_statusfor detailed status info.Extract text from a single local image with
extract_text_umi_v2.OCR directly from a Base64-encoded image with
ocr_image_base64, avoiding temporary files.Batch OCR multiple local images in one call with
ocr_batch.Scan and OCR all images in a directory, optionally recursively, with
ocr_directory.OCR a specific PDF page directly via
ocr_pdf_page, with configurable DPI and confidence threshold.Control OCR quality through confidence thresholds, including lower thresholds for handwriting.
Use built-in MCP prompt templates for quick single-image OCR, PDF workflows, and batch document processing.
Automatically detect, start, and keep alive the Umi-OCR process, with built-in OCR text post-processing corrections.
Integrates Umi-OCR local OCR capabilities into Hermes AI agent, enabling image text extraction, batch OCR, PDF OCR, and directory scanning through MCP.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@Umi-OCR MCP Serverextract text from D:\photos\document.png"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Umi-OCR MCP Server
Expose the local OCR capabilities of Umi-OCR v2 to AI Agents (Hermes, Claude Code, Codex, etc.) via the MCP protocol.
Automatically launches the Umi-OCR process — no need to start the service manually.
Directory Structure
Umi-OCR-MCP/
├── server.py # MCP 服务器(核心)
├── pyproject.toml # 依赖声明(uv run 自动安装)
├── requirements.txt # pip 依赖声明(备选)
├── config.yaml # Hermes config 接入模板
└── README.mdRelated MCP server: Kimi Vision MCP Server
Prerequisites
Dependency | Description |
Umi-OCR v2.1.5+ | Download the Paddle version (recommended) from umi-ocr.com, install it, then enable the HTTP API (Settings -> Service -> Enable HTTP API, default port 1224) |
Python 3.11+ | Recommended to manage via uv |
uv | Package manager, used by |
Quick Start
1. Confirm the Umi-OCR Path
Default path: YOUR_UMI_OCR_PATH\Umi-OCR.exe
If different, specify it via the environment variable UMI_OCR_EXE.
Windows note: if the path contains Chinese characters, spaces, or special characters, make sure to escape them correctly in YAML and environment variables.
2. Test the MCP Service
cd YOUR_PROJECT_PATH\Umi-OCR-MCP
uv run server.pyThe first uv run automatically reads pyproject.toml, creates a temporary virtual environment, and installs the mcp and requests dependencies.
3. Connect to Hermes Agent
Merge the contents of config.yaml into the mcp_servers section of Hermes' config.yaml:
mcp_servers:
umi-ocr-mcp:
command: uv
args:
- run
- --directory
- YOUR_PROJECT_PATH/Umi-OCR-MCP
- YOUR_PROJECT_PATH/Umi-OCR-MCP/server.py
env:
UMI_OCR_URL: "http://127.0.0.1:1224/api/ocr"
UMI_OCR_EXE: "YOUR_UMI_OCR_PATH\\Umi-OCR.exe"Key point: the
--directoryargument tells uv where to findpyproject.toml— it cannot be omitted. Without it, uv cannot find the dependencies and will directly raise ModuleNotFoundError.
Path format: forward slashes are recommended, e.g.
D:/path/to/. Backslashes must be escaped in YAML asD:\\path\\to\\.
How It Works
AI Agent -> MCP stdio -> server.py
1. 检测端口 1224 是否开放
2. 未开放 -> 自动启动 Umi-OCR.exe(指数退避等待,最长 30s)
3. 开放 -> 调用 HTTP API 识别图片
4. OCR 文本 -> 置信度过滤(>0.85)
5. 轻量后处理(常见 OCR typo 修正)
6. 返回纯文本给 AgentService Keep-Alive
Each call to extract_text_umi_v2 automatically checks the port. If the Umi-OCR process exits unexpectedly, the next call will automatically relaunch it — no manual intervention needed.
Post-Processing Rules
Built-in regex replacements that fix unambiguous, common OCR errors (things that don't affect AI understanding are left untouched):
Original | Corrected |
packspace | backspace |
AMDV | AMD-V |
Windows102004 | Windows 10 2004 |
打并 | 打开 |
重新新 | 重新 |
Post-processing only fixes OCR noise that is certain. Anything outside the rule scope is left as-is for the AI to interpret.
FAQ
ModuleNotFoundError: No module named 'requests'
uv run uses an isolated environment by default and cannot see globally installed packages.
Solution: the project already includes pyproject.toml. Make sure to launch with uv run --directory <project directory> — uv will install the dependencies automatically.
Umi-OCR Startup Timeout
Check that the
UMI_OCR_EXEpath is correctThe first launch of Umi-OCR needs to load the PaddleOCR model; slower machines may need 15-30 seconds
You can enable "Start on boot" or "Minimize to tray" in Umi-OCR settings to avoid waiting each time
API Returns an Error Code
Umi-OCR v2 API format:
POST /api/ocr
{"base64": "<base64字符串>"}Returns:
{"code": 100, "data": [{"text":"...","score":0.99}], "msg":"success"}code=100: success
code=300: Base64 decoding failed (an array was passed instead of a string)
code=802: missing base64 field
Deploying on Other Machines
Install uv
Install Umi-OCR (download the Paddle version from umi-ocr.com) and enable the HTTP API (port 1224)
Modify the default paths in
config.yamlandserver.pyConfirm port 1224 is not occupied
The first
uv runneeds network access to auto-download dependencies
API Reference
Tool Overview
Tool | Purpose | Category | Token Characteristics |
| Minimal service status | Check | Only ~5 chars output |
| Full service status | Check | ~200 chars output |
| OCR for a single image | Core | Standard output |
| OCR directly from Base64 | Core | Skips the file-writing step |
| Batch OCR for multiple images | Batch | One call handles multiple images |
| Directory-scan batch OCR | Batch | Skips list + manifest building |
| OCR a single PDF page directly | Skips rendering + saving steps |
quick_ocr_status
Minimal status check, suitable for high-frequency polling.
参数:
无
返回:
"running" | "stopped" | "error: ..."Token comparison: ~5 chars vs ~200 chars for check_ocr_status — saves 97%.
check_ocr_status
Full service status information.
参数:
无
返回:
服务运行状态、监听地址、API 端点、可执行文件路径extract_text_umi_v2
OCR to extract text from a local image. Includes built-in paragraph merging and confidence filtering.
参数:
file_path: str -- 图片绝对路径(必填)
is_handwritten: bool -- 是否手写笔记,默认 False
返回:
str -- 识别文本,或错误信息ocr_image_base64
Extract text directly from a Base64-encoded image, skipping the file-writing step.
参数:
image_base64: str -- Base64 编码字符串(含 data URL 前缀亦可)
is_handwritten: bool -- 是否手写笔记,默认 False
返回:
str -- 识别文本,或错误信息ocr_batch
Batch OCR for multiple local images; one call returns all results.
参数:
file_paths: List[str] -- 图片绝对路径列表
is_handwritten: bool -- 是否手写笔记,默认 False
返回:
str -- 按输入顺序的分隔线分区结果ocr_directory ⭐ New in v1.1
Scans all images in a directory and performs batch OCR. In recursive mode, subdirectories are handled too.
参数:
directory_path: str -- 目录绝对路径(必填)
extensions: str -- 逗号分隔的扩展名,默认 "png,jpg,jpeg,bmp,webp"
recursive: bool -- 是否递归子目录,默认 False
is_handwritten: bool -- 是否手写笔记,默认 False
confidence_threshold: float -- 置信度阈值,默认 0.85
返回:
str -- 紧凑格式:[总数] + 文件名 + 文本ocr_pdf_page ⭐ New in v1.1
Directly renders a specified PDF page as an image and OCRs it in one step. Depends on PyMuPDF.
参数:
pdf_path: str -- PDF 文件绝对路径(必填)
page_number: int -- 页码(1-based),默认 1
is_handwritten: bool -- 是否手写笔记,默认 False
dpi: int -- 渲染分辨率,默认 200
confidence_threshold: float -- 置信度阈值,默认 0.85
返回:
str -- 识别文本,或错误信息Confidence Threshold Notes
All OCR tools internally use confidence_threshold to filter out low-quality results.
When you need direct control, use the parameter exposed by the new tools:
Scenario | Recommended Threshold | Description |
Clear printed text | 0.90+ | Extremely high precision, better to miss than to err |
Standard documents | 0.85 (default) | Balance between precision and recall |
Scanned workbooks | 0.70-0.80 | Paper quality varies, needs more tolerance |
Handwritten notes | 0.60-0.75 | Handwriting recognition rates are naturally lower |
MCP Fixed Instructions (Prompts)
The MCP protocol supports Prompts — predefined fixed instruction templates.
The Agent retrieves them via the dedicated tool get_prompt(name), which returns standardized step-by-step workflow instructions.
server.py ships with 3 built-in Prompts covering the most common OCR scenarios.
Calling Them in Hermes
After restarting the MCP connection, Hermes automatically registers the mcp__umi_ocr__get_prompt tool.
Call it like this:
# 列出所有可用 Prompt
mcp__umi_ocr__list_prompts()
# 调取特定 Prompt
mcp__umi_ocr__get_prompt(name="ocr-workflow-quick")Prompts return instruction text (not execution results). The Agent reads them and then calls the corresponding Tools step by step to perform the actual OCR.
ocr-workflow-quick
Standard workflow for quick OCR of a single image.
Step | Action | Tool |
1 | Confirm the service is online |
|
2 | Extract text |
|
3 | Poor quality → retry with lower threshold |
|
Applies to: screenshots, a single exam-paper photo, photos of a whiteboard.
ocr-workflow-pdf
Standard workflow for page-by-page PDF OCR.
Step | Action | Tool |
1 | Confirm the service is online |
|
2 | OCR page 1 to probe quality |
|
3 | Blurry text → raise DPI to 300 |
|
4 | Many missing characters → lower threshold to 0.70 |
|
5 | Quality OK → extract page by page | Loop |
Applies to: scanned college-entrance-exam PDFs, digital workbooks, papers.
ocr-workflow-batch
Standard workflow for batch OCR of a full workbook / exam-paper set.
Step | Action | Tool |
1 | Confirm the service is online |
|
2 | Scan all images in the directory |
|
3 | Spot-check 2-3 results | Human or Agent judges the quality |
4 | Individual failures → retry individually |
|
5 | Assemble into a full document | Merge by sorting file names |
Applies to: a full textbook scanned page-by-page into multiple images, multi-page exam-paper collections.
Available Tools
7 toolscheck_ocr_statusA
检查 Umi-OCR 服务是否在运行以及基本状态信息。
节省 token 场景:在发起重要的 OCR 任务前,先确认服务可用, 避免在服务未启动时发起多次失败的 OCR 调用。
返回: 服务运行状态、监听地址、可执行文件路径等信息。
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description discloses return information (status, address, path). It could mention idempotency or non-destructiveness, but the provided context is adequate for a read-only check.
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 well-structured with purpose, usage guidance, and return info in separate sections. It is concise, though the '节省 token 场景' line could be integrated more tightly.
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 no parameters and an output schema, the description covers the key return fields in plain language. It lacks details on error handling or potential network issues but is otherwise sufficient.
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?
No parameters exist, so the description naturally adds no parameter info. Schema coverage is 100%, meeting the baseline and earning a high score.
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 checks the Umi-OCR service status, with a specific verb ('检查') and resource ('Umi-OCR 服务'). It distinguishes from siblings like 'quick_ocr_status' by providing context for usage before OCR tasks.
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?
Explicitly advises using this tool before important OCR tasks to confirm service availability and avoid token waste, providing clear when-to-use context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
extract_text_umi_v2A
调用 Umi-OCR v2.1.5 提取本地图片文本。 已内置段落合并与置信度过滤,极致节约 Token。 专为 AI 阅读理解优化:自动按 Umi-OCR 段落规则分块 + 轻量后处理。
参数: file_path: 图片的绝对本地路径 is_handwritten: 是否手写笔记(切换手写模型),默认 False
| Name | Required | Description | Default |
|---|---|---|---|
| file_path | Yes | ||
| is_handwritten | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
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. It discloses key behaviors: automatic paragraph merging, confidence filtering, token saving, and handwriting model switching. This provides sufficient transparency for a read-only tool without destructive side effects.
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 concise (three lines for purpose, two for bullet features, two for params) with clear structure and no redundant text. Every sentence adds value, making it easy for an AI 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 simplicity (2 parameters, output schema present), the description covers the core functionality and parameter guidance. It lacks return format details, but the output schema fills that gap. Overall, it is sufficiently complete for standard 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 schema has 0% description coverage, so the description must compensate. It meaningfully explains both parameters: file_path as 'absolute local path' and is_handwritten as 'switch handwriting model', adding context beyond the schema fields. This is adequate for the two parameters.
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 extracts text from local images using Umi-OCR v2.1.5, with specific features like paragraph merging and confidence filtering. It distinguishes from sibling tools (e.g., ocr_batch, ocr_directory) that handle different inputs or batch processing, making the purpose unambiguous.
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 specifies the tool is optimized for AI reading and automatically processes paragraphs, implying its use for single-image text extraction with built-in preprocessing. However, it does not explicitly state when not to use it or suggest alternatives, though sibling names provide implicit guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ocr_batchA
批量 OCR 多张本地图片,一次调用返回所有结果。
节省 token 场景:需要 OCR 多张图片时,避免多次 MCP 调用的 往返开销,将多张图片合并为一次调用。
参数: file_paths: 图片的绝对本地路径列表 is_handwritten: 是否手写笔记,默认 False
返回: 按输入顺序返回每张图片的 OCR 结果,用分隔线区隔。
| Name | Required | Description | Default |
|---|---|---|---|
| file_paths | Yes | ||
| is_handwritten | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden. It discloses that results are returned in input order and separated by delimiters, which is helpful. However, it does not mention error handling for individual image failures, size limits, or timeouts, leaving gaps for a mutation-like batch operation.
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 concise and well-structured: a one-line purpose, a usage note, parameter descriptions, and return format. Every sentence adds value with no fluff, achieving high information density.
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 simplicity (2 parameters, no annotations), the description covers purpose, usage, parameters, and return format. It lacks details on error handling, prerequisites (e.g., file existence), and limits, but the presence of an output schema mitigates the need to explain return values. Overall, sufficient for typical 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 coverage is 0%, so the description must compensate. It provides clear descriptions for both parameters: 'file_paths: absolute local path list' and 'is_handwritten: whether handwritten notes, default False'. This adds meaningful context beyond the schema's type and title, fully covering parameter semantics.
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 explicitly states 'Batch OCR multiple local images, one call returns all results', which clearly defines the action (batch OCR) and the resource (local images). It distinguishes this tool from siblings that handle single images, PDF pages, or directories, making the purpose unambiguous.
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 clear use case: 'Save token scenario: When needing to OCR multiple images, avoid multiple MCP call round-trips by merging into one call.' This guides when to use the tool. However, it does not explicitly exclude cases where seperate calls might be better (e.g., incremental results), which keeps it from a perfect score.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ocr_directoryA
批量 OCR 目录下所有图片。
节省 token 场景:无需先列出目录再构建文件列表,一步完成 目录扫描 + 批量 OCR。适合整本扫描版教辅的批量提取。
参数: directory_path: 目录绝对路径 extensions: 逗号分隔的扩展名(不含点),默认 png,jpg,jpeg,bmp,webp recursive: 是否递归子目录,默认 False is_handwritten: 是否手写笔记,默认 False confidence_threshold: 置信度阈值,默认 0.85
返回: 按文件名排序的识别结果,紧凑格式(总数 + 文件名 + 文本)。
| Name | Required | Description | Default |
|---|---|---|---|
| recursive | No | ||
| extensions | No | png,jpg,jpeg,bmp,webp | |
| directory_path | Yes | ||
| is_handwritten | No | ||
| confidence_threshold | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description partially covers behavior: it mentions sorting by filename, compact format, and parameter defaults. However, it does not disclose side effects (e.g., file modification), error handling, or performance characteristics for large directories.
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 concise and well-structured: a one-line summary, a brief use-case note, and a clean parameter list. Every sentence adds value, no redundant words.
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 5 parameters, 1 required, and an output schema, the description covers purpose, parameters, and return format (sorted, compact). It lacks details on permissions, file size limits, or error scenarios, but is adequate for a typical 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 coverage is 0%, but the description fully explains all 5 parameters: directory_path, extensions with default, recursive, is_handwritten (handwritten notes), and confidence_threshold. This adds clear meaning beyond the schema's type/default fields.
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 and resource: '批量 OCR 目录下所有图片' (batch OCR all images in a directory). It highlights the one-step nature (directory scan + batch OCR) and distinguishes from siblings like ocr_batch and ocr_image_base64 by focusing on directory-level input.
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 suggests a use case: saving tokens by avoiding separate directory listing, and indicates suitability for batch extraction from scanned books. However, it does not explicitly compare with sibling tools or state when not to use.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ocr_image_base64B
直接从 base64 编码的图片中提取文本。
节省 token 场景:当图片已经以 base64 形式存在(如粘贴板、 其他工具返回的图片数据)时,省去写入文件的步骤, 一步 OCR 到文本。
参数: image_base64: 图片的 base64 编码字符串(含或不含 data URL 前缀均可) is_handwritten: 是否手写笔记,默认 False
| Name | Required | Description | Default |
|---|---|---|---|
| image_base64 | Yes | ||
| is_handwritten | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
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 input format and parameter defaults but omits output format, error handling, rate limits, or size constraints. The output schema exists but the description does not reference return values.
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 concise with a clear structure: purpose, use case, parameter list. Each sentence adds value, though the token-saving scenario could be inferred. No unnecessary repetition.
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 simplicity (2 params, no nesting) and existence of an output schema, the description is adequate but incomplete. It lacks mention of return values or error scenarios, requiring the agent to rely on the output 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 0%, but the description adds meaning: image_base64 clarifies prefix allowance ('含或不含 data URL 前缀均可') and is_handwritten explains default false. This compensates for the schema's lack of 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 states 'Extract text directly from base64 encoded images', clearly specifying the verb and resource. It distinguishes from sibling tools (e.g., ocr_directory, ocr_pdf_page) by implying base64 input, but does not explicitly compare 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 explains a token-saving scenario when base64 is already available ('当图片已经以 base64 形式存在...省去写入文件步骤'). This provides usage context but lacks explicit when-not-to-use or comparison with siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ocr_pdf_pageA
OCR 提取 PDF 指定页文本。
节省 token 场景:绕过 PDF→截图→存文件→OCR 的多步工作流, 一步到位。对常见的高考真题 PDF、扫描版教辅尤为高效。
参数: pdf_path: PDF 文件绝对路径 page_number: 页码(1-based,默认第 1 页) is_handwritten: 是否手写笔记,默认 False dpi: 渲染分辨率,默认 200(OCR 精度与速度的平衡点) confidence_threshold: 置信度阈值,默认 0.85
返回: 识别文本或错误信息
| Name | Required | Description | Default |
|---|---|---|---|
| dpi | No | ||
| pdf_path | Yes | ||
| page_number | No | ||
| is_handwritten | No | ||
| confidence_threshold | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so description carries full burden. Describes core behavior, parameters affecting output (e.g., is_handwritten, confidence_threshold), and return type (text or error). Lacks mention of limitations like file size or language support, but sufficient for basic usage.
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?
Well-structured with a concise purpose statement, usage scenario, parameter list, and return info. Every sentence adds value; no redundancy.
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 5 parameters (1 required), no annotations, and expected output, the description fully covers parameter semantics, usage context, and return values. No obvious gaps for a tool of this complexity.
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%, but description thoroughly explains each parameter: pdf_path, page_number, is_handwritten, dpi, and confidence_threshold, including defaults and rationale for dpi as a balance between accuracy and speed. Adds significant value beyond schema.
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?
Clearly states the tool's function: OCR extraction of text from a specified PDF page. Distinguishes from sibling tools by emphasizing direct PDF page OCR versus other OCR methods like image-based or batch processing.
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?
Provides explicit scenarios where the tool is beneficial (saving tokens by bypassing multi-step workflow, especially for exam PDFs and scanned textbooks). Does not specify when not to use, but context is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
quick_ocr_statusA
极简状态检查,仅返回 "running" 或 "stopped"。
节省 token 场景:替代 check_ocr_status 的完整输出(~200 tokens), 仅需 ~10 tokens 确认服务状态。适用于高频轮询场景。
返回: "running" 或 "stopped" 或 "error: ..."
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. It states the return values (running/stopped/error) and the performance trade-off (saves tokens). However, it does not specify what causes errors, permissions required, or side effects, but for a simple read-only status check, this is sufficient.
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: two sentences and a return type list. Core information is front-loaded, and every sentence adds value. No wasted text.
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 no parameters and a simple output, the description fully covers the tool's purpose, output format, and usage trade-offs. It references a sibling tool for context and mentions error cases. Output schema existence is noted, but description independently explains the return type.
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?
There are zero parameters, so the schema coverage is 100%. The description adds no parameter details, but none are needed. Baseline of 4 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?
Description clearly states the tool checks OCR service status and returns either 'running' or 'stopped'. It distinguishes itself from sibling 'check_ocr_status' by being a minimal, token-saving alternative, making the purpose and unique value immediately apparent.
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?
Explicitly recommends using this tool for high-frequency polling scenarios to save tokens, and identifies 'check_ocr_status' as the alternative when more detail is needed. This provides clear when-to-use and when-not-to-use guidance.
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.
7 tool updates
v1.0.0- First observed
check_ocr_status - First observed
extract_text_umi_v2 - First observed
ocr_batch - First observed
ocr_directory - First observed
ocr_image_base64 - First observed
ocr_pdf_page - First observed
quick_ocr_status
TDQS
Scored across 7 tools
Tools are mostly distinct: OCR methods target different input types (file, base64, PDF, batch, directory). The two status-check tools serve different granularities (detailed vs quick), but their overlap could cause slight confusion despite clear descriptions.
Naming is inconsistent: some tools use 'ocr_' prefix (ocr_batch, ocr_directory), others use different patterns (check_ocr_status, quick_ocr_status, extract_text_umi_v2). The 'extract_text_umi_v2' name includes a version suffix, breaking convention.
With 7 tools, the set is well-scoped for an OCR server. Each tool has a clear role: status checks, single-image OCR from various sources, batch, and directory scanning. No unnecessary tools.
Covers the main OCR workflow: status check, single image from file/base64/PDF, batch, and directory. Minor gaps like multi-page PDF OCR or clipboard input are absent but not critical for the core use case.
Maintenance
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