fit-device-id-modifier

Modify FIT files to set device manufacturer to Garmin (1) and product ID to Edge 500 China (1030) for proper recognition on Garmin Connect.

Security Scan

The code and instructions do what the skill says (modify FIT file manufacturer/product and write _GM.fit copies); there are no unexpected network calls, credentials, or installs, but the implementation uses a naive binary search-and-replace and a custom CRC routine so you should back up files and test before wide use.

Purpose & Capability

Name, description, SKILL.md, and the included modify_fit.py are consistent: the skill reads FIT files, sets manufacturer to 1 and garmin_product to 1030, recalculates CRC, and writes new *_GM.fit files. The only external dependency mentioned is fitparse (pip), which is appropriate for parsing FIT files.

Instruction Scope

Runtime instructions only ask the agent/user to run the provided Python script against FIT files. The script only reads local files and writes new files; it prints message/field values to stdout. Caveats: the script performs binary replacement by searching for the old numeric value's byte sequence anywhere in the file (data.find) which can accidentally replace unrelated occurrences, and it uses a custom CRC calculation that may not match the official FIT CRC algorithm. SKILL.md references an absolute conda/python path and to run from a specific workspace directory — these are benign but environment-specific and should be adjusted to your system.

Install Mechanism

There is no install spec (instruction-only skill with a Python script). The only required package is fitparse (pip), which is reasonable and expected. No remote downloads or archives are fetched by the skill itself.

Credentials

The skill does not request environment variables, credentials, or config paths. SKILL.md mentions a local Python interpreter path but that is an instruction, not a secret. No access to unrelated services is requested.

Persistence & Privilege

always is false and the skill does not attempt to modify other skills or system-wide configuration. It only operates on files given to it and writes per-file outputs.

Assessment

This skill appears to be what it says: a local tool to modify FIT files so Garmin Connect recognizes them. Before using it widely: 1) Back up original FIT files (the script can corrupt files because it replaces raw byte sequences and may match unintended bytes). 2) Test on a small sample and verify the generated _GM.fit is accepted by Garmin Connect. 3) Use an isolated Python environment and pip install fitparse rather than running the absolute /home/ckboss path in the SKILL.md. 4) Review/consider improving the script (identify fields by message structure rather than byte-pattern search and verify the CRC algorithm matches the FIT specification). 5) There are no network calls or credential requests in the code, so there is low privacy risk, but always inspect outputs before uploading to external services.

修改 FIT 文件的设备 ID（manufacturer 和 garmin_product），将骑行记录转换为 Garmin Edge 500 China 设备生成的格式。

用途

• 修改 FIT 文件中的 manufacturer 字段为 1 (Garmin)
• 修改 garmin_product 字段为 1030 (Edge 500 China)
• 用于让第三方骑行软件生成的 FIT 文件能被 Garmin Connect 等平台正确识别

依赖

• Python 3.x
• fitparse 库 (pip install fitparse)

使用方法

批量处理子目录中的 FIT 文件

cd /home/ckboss/.openclaw/workspace/skills/fit-device-id-modifier/scripts
/home/ckboss/anaconda3/bin/python modify_fit.py

这会处理 ./ */*.fit 匹配的所有 FIT 文件，生成 _GM.fit 后缀的修改版。

处理单个文件

/home/ckboss/anaconda3/bin/python modify_fit.py /path/to/ride.fit

处理整个目录

/home/ckboss/anaconda3/bin/python modify_fit.py /path/to/rides/

输出

• 原文件保持不变
• 生成新文件：原文件名_GM.fit

注意事项

• 会自动跳过已处理的文件（文件名包含 _GM.fit）
• 会重新计算 CRC 校验和确保文件完整性
• 使用 conda Python：/home/ckboss/anaconda3/bin/python

文件结构

skills/fit-device-id-modifier/
├── SKILL.md
└── scripts/
    └── modify_fit.py