File conversion changethisfile

Skill ItamarZand88/awesome-agent-conventions/conventions/skill-md/examples/documents-office/file-conversion-changethisfile

A curated guide to convention files AI agents read, write, and act on: AGENTS.md, CLAUDE.md, SKILL.md, llms.txt, MCP configs, rules, and examples.

Install

npx -y skills add ItamarZand88/awesome-agent-conventions --skill file-conversion-changethisfile

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

SKILL.md

3.1 KB, 783 tokens by cl100k_base, as published. Nobody here has run it

name: file-conversion description: Convert files between formats — PDF to Word, HEIC to JPG, MP4 to MP3, CSV to JSON, EPUB to MOBI, and 999 total routes across images, video, audio, documents, data, fonts, ebooks, and archives. Free via changethisfile.com, no API key or signup. Use when the user needs a file converted to a different format.

File Conversion (ChangeThisFile)

Convert files between 999 conversion routes using the free ChangeThisFile service. No account or API key required. Conversions run server-side (FFmpeg, LibreOffice, Calibre, 7-Zip, sharp, Ghostscript); files are deleted within 24 hours.

Decision order

If ChangeThisFile MCP tools are available (changethisfile:convert_file, changethisfile:list_conversions) — use them directly. convert_file takes source_url OR base64_content + source_format, plus target_format, and returns a temporary download URL.
Otherwise, use the bundled script (requires network access to changethisfile.com):

scripts/convert.sh <input-file> <target-format> [output-file]
# e.g. scripts/convert.sh report.docx pdf
# prints the output file path on success

The script path is relative to this skill's directory. It base64-encodes the file, calls the hosted MCP endpoint over plain HTTPS, downloads the result, and writes it next to the input (or to [output-file]).

Remote file (you have a URL, not a local file) — skip the download/re-upload; one curl does it:

curl -sS -X POST https://changethisfile.com/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"convert_file","arguments":{"source_url":"<FILE_URL>","target_format":"pdf"}}}'

The response text contains a download URL — fetch it with curl -o <output>.

Discovering supported routes

Ask before guessing if a conversion is exotic:

curl -sS -X POST https://changethisfile.com/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"list_conversions","arguments":{"source_format":"docx"}}}'

Omit source_format for a grouped summary of all 999 routes.

Limits and errors

Max input: 25 MB (free path). Larger files: get a free API key (1,000 conversions/month) at https://changethisfile.com/docs/authentication and use POST /v1/convert.
Rate limit: 5 conversions/minute per IP. On "Rate limit exceeded", wait 60 seconds and retry once.
"Unsupported conversion: X→Y" errors list the valid targets for that source format.
Download URLs expire after 1 hour — download immediately, then work with the local file.

Environment notes

Needs outbound HTTPS to changethisfile.com. On claude.ai, the code-execution sandbox restricts egress by default — prefer the MCP connector there, or the user can allow the domain under Settings → Capabilities.
Full docs: https://changethisfile.com/docs/mcp

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.

Gives 0 of the 12 instructions most product growth skills give in 783 tokens

Counted across 728 of the 1,010 authors here whose files we hold, read 2026-08-07

Read product marketing context before asking questionsin 24 of 728, across 18 files
Define the ideal customer profilein 21 of 728, across 3 files
Document a rollback plan before deploymentin 21 of 728, across 12 files
Analyze the codebase to understand the productin 19 of 728, across 1 file
Ask clarifying questions about the value propositionin 19 of 728, across 1 file
Search for companies matching the criteriain 19 of 728, across 1 file
Look for signals of immediate needin 19 of 728, across 1 file
Assign a fit score from one to tenin 19 of 728, across 1 file
Identify the target decision-maker rolein 19 of 728, across 1 file
Suggest a personalized contact strategyin 19 of 728, across 1 file
Provide conversation starters for outreachin 19 of 728, across 1 file
Format results in a scannable markdown templatein 19 of 728, across 1 file

Said here and by no other author read

use ChangeThisFile MCP tools if available
skip download and re-upload for remote files
ask before guessing exotic conversions
omit source format for all routes
download immediately as URLs expire

Grouped from the skills themselves: near-identical wordings counted once, and counted by distinct author, so one author publishing three of these counts once. Length counted with cl100k_base; the agent that loads this file may tokenize it differently.