Agents

Agent skill

One markdown file. Drop it into your agent's skills directory and it knows the whole API — the endpoints, the credit costs, and the handful of things that trip people up. For agents that can run a shell but do not speak MCP, which today is most of them.

Download apkcube.md View it first

On this page

Install
What it works with
What it looks like in use
Why not an SDK

Install#

Fetch it into a skills directory

mkdir -p .claude/skills/apkcube
curl -sS https://apkcube.com/skill/apkcube.md -o .claude/skills/apkcube/SKILL.md
export APKCUBE_API_KEY="akc_9f3Ka2Lp_xxxxxxxxxxxxxxxxxxxx"

# Any agent that reads instruction files: put it where yours looks.
curl -sS https://apkcube.com/skill/apkcube.md -o apkcube.md
export APKCUBE_API_KEY="akc_9f3Ka2Lp_xxxxxxxxxxxxxxxxxxxx"

What it works with#

The only thing that decides this is whether your agent can make an HTTP request by itself.

Works

Claude Code, and anything else with shell access
Cursor and Windsurf in agent mode
Any agent framework that can run curl or fetch
Coding agents in CI, given the key as an environment variable

Can read it, cannot run it

Chat interfaces with no shell and no network tool — they can read the file and explain it, but not run it
Anything sandboxed without outbound HTTPS

What it looks like in use#

You ask for something in plain language; the agent works out the calls. Asking for the newest Signal build, for instance, becomes three requests it makes on its own: search for the package, list its versions, then mint a URL for the one that matches.

What the agent ends up running

BASE="https://apkcube.com/api/v1"
AUTH="Authorization: Bearer $APKCUBE_API_KEY"

curl -sS -H "$AUTH" "$BASE/apps?q=signal" | jq -r '.items[0].packageName'
# org.thoughtcrime.securesms

curl -sS -H "$AUTH" "$BASE/apps/org.thoughtcrime.securesms/versions" \
  | jq '.versions[] | select(.arch=="arm64-v8a") | {apkId, versionName, fileSize}'

curl -sS -X POST -H "$AUTH" -H "Content-Type: application/json" \
  -d '{"apkId":"48211"}' "$BASE/apps/org.thoughtcrime.securesms/download" | jq -r .url

Why a skill file and not an SDK#

Because an SDK would be worse here, not because one was too much work.

No language lock-in. The agent writes whatever it already writes — Python, Go, a shell one-liner. A TypeScript SDK helps only the agents working in TypeScript.
No version to pin. The file is fetched from here, so it describes the API as it is now. There is no release to upgrade and no lockfile to go stale.
It teaches the traps. The useful part is not the endpoint list, which the OpenAPI spec already covers — it is that installs is a string, that XAPKs are not adb install-able, and that a download costs 10 credits so you should check availability first. Those belong in prose an agent reads, not in type signatures.

Agent skill

Install#

Fetch it into a skills directory

mkdir -p .claude/skills/apkcube
curl -sS https://apkcube.com/skill/apkcube.md -o .claude/skills/apkcube/SKILL.md
export APKCUBE_API_KEY="akc_9f3Ka2Lp_xxxxxxxxxxxxxxxxxxxx"

# Any agent that reads instruction files: put it where yours looks.
curl -sS https://apkcube.com/skill/apkcube.md -o apkcube.md
export APKCUBE_API_KEY="akc_9f3Ka2Lp_xxxxxxxxxxxxxxxxxxxx"

What it works with#

The only thing that decides this is whether your agent can make an HTTP request by itself.

Works

Claude Code, and anything else with shell access
Cursor and Windsurf in agent mode
Any agent framework that can run curl or fetch
Coding agents in CI, given the key as an environment variable

Can read it, cannot run it

Chat interfaces with no shell and no network tool — they can read the file and explain it, but not run it
Anything sandboxed without outbound HTTPS

What it looks like in use#

What the agent ends up running

BASE="https://apkcube.com/api/v1"
AUTH="Authorization: Bearer $APKCUBE_API_KEY"

curl -sS -H "$AUTH" "$BASE/apps?q=signal" | jq -r '.items[0].packageName'
# org.thoughtcrime.securesms

curl -sS -H "$AUTH" "$BASE/apps/org.thoughtcrime.securesms/versions" \
  | jq '.versions[] | select(.arch=="arm64-v8a") | {apkId, versionName, fileSize}'

curl -sS -X POST -H "$AUTH" -H "Content-Type: application/json" \
  -d '{"apkId":"48211"}' "$BASE/apps/org.thoughtcrime.securesms/download" | jq -r .url

Why a skill file and not an SDK#

Because an SDK would be worse here, not because one was too much work.

No language lock-in. The agent writes whatever it already writes — Python, Go, a shell one-liner. A TypeScript SDK helps only the agents working in TypeScript.

No version to pin. The file is fetched from here, so it describes the API as it is now. There is no release to upgrade and no lockfile to go stale.

It teaches the traps. The useful part is not the endpoint list, which the OpenAPI spec already covers — it is that installs is a string, that XAPKs are not adb install-able, and that a download costs 10 credits so you should check availability first. Those belong in prose an agent reads, not in type signatures.