Exercise Library Skill
The tool
Give your agent a full exercise database. Call it as an MCP tool to look up movements by muscle and equipment with instructions and difficulty.
Once your client is connected to the VerveKit MCP server, this appears in its tool list as ExerciseLibrarySkill. It is read-only and open-world: it fetches, it never mutates anything on your side, so most clients will call it without asking you to confirm.
{
"name": "ExerciseLibrarySkill",
"arguments": {
"muscle": "chest"
}
}What that looks like in a conversation
You don't name the tool — the model picks it. Asking about chest in the terms this source covers is enough for it to reach for ExerciseLibrarySkill on its own.
Connecting
One server URL covers every skill in the catalog, including this one. Authorization is OAuth — the client opens a browser once and there is no key to paste into a config file.
{
"mcpServers": {
"vervekit": {
"url": "https://api.vervekit.com/v1/mcp"
}
}
}https://api.vervekit.com/v1/mcpPer-client setup — Claude Desktop, Cursor, VS Code, ChatGPT — is on the MCP setup page.
Arguments
These are the properties on the tool's inputSchema, so a well-behaved client validates them before the call is made.
| Argument | Type | Example | Description |
|---|---|---|---|
muscleRequired | string | chest | The muscle group to get exercises for One of: abdominals, abductors, adductors, biceps, calves, chest, forearms, glutes. |
name | string | barbell | The name of the exercise to get information about |
equipment | string | barbell | The equipment used for the exercise One of: barbell, dumbbell, cable, machine, body_only, kettlebells, bands, foam_roll. |
What the model gets back
The result carries a structuredContent object matching the tool's declared outputSchema, so a client can read fields without parsing prose. status is "ok" on success and error is null; a null field means the value wasn't available for that input, not that the call failed.
{
"status": "ok",
"error": null,
"data": {
"count": 5,
"filteredOn": [
"name",
"muscle"
],
"exercises": [
{
"name": "Barbell Ab Rollout",
"force": "pull",
"level": "intermediate",
"mechanic": "compound",
"equipment": "barbell",
"instructions": [
"For this exercise you will need to get into a pushup position, but instead of having your hands of the floor, you will be grabbing on to an Olympic barbell (loaded with 5-10 lbs on each side) instead. This will be your starting position.",
"While keeping a slight arch on your back, lift your hips and roll the barbell towards your feet as you exhale. Tip: As you perform the movement, your glutes should be coming up, you should be keeping the abs tight and should maintain your back posture at all times. Also your arms should be staying perpendicular to the floor throughout the movement. If you don't, you will work out your shoulders and back more than the abs.",
"After a second contraction at the top, start to roll the barbell back forward to the starting position slowly as you inhale.",
"Repeat for the recommended amount of repetitions."
],
"muscle": "biceps"
},
{
"name": "Barbell Ab Rollout - On Knees",
"force": "pull",
"level": "expert",
"mechanic": "compound",
"equipment": "barbell",
"instructions": [
"Hold an Olympic barbell loaded with 5-10lbs on each side and kneel on the floor.",
"Now place the barbell on the floor in front of you so that you are on all your hands and knees (as in a kneeling push up position). This will be your starting position.",
"Slowly roll the barbell straight forward, stretching your body into a straight position. Tip: Go down as far as you can without touching the floor with your body. Breathe in during this portion of the movement.",
"After a second pause at the stretched position, start pulling yourself back to the starting position as you breathe out. Tip: Go slowly and keep your abs tight at all times."
],
"muscle": "biceps"
},
{
"name": "Barbell Bench Press - Medium Grip",
"force": "push",
"level": "beginner",
"mechanic": "compound",
"equipment": "barbell",
"instructions": [
"Lie back on a flat bench. Using a medium width grip (a grip that creates a 90-degree angle in the middle of the movement between the forearms and the upper arms), lift the bar from the rack and hold it straight over you with your arms locked. This will be your starting position.",
"From the starting position, breathe in and begin coming down slowly until the bar touches your middle chest.",
"After a brief pause, push the bar back to the starting position as you breathe out. Focus on pushing the bar using your chest muscles. Lock your arms and squeeze your chest in the contracted position at the top of the motion, hold for a second and then start coming down slowly again. Tip: Ideally, lowering the weight should take about twice as long as raising it.",
"Repeat the movement for the prescribed amount of repetitions.",
"When you are done, place the bar back in the rack."
],
"muscle": "biceps"
},
{
"name": "Barbell Curl",
"force": "pull",
"level": "beginner",
"mechanic": "isolation",
"equipment": "barbell",
"instructions": [Fields
| Field | Type | Example | Description |
|---|---|---|---|
count | number | 5 | Total number of exercises returned |
filteredOn | array | ["name","muscle"] | Fields used to filter exercise results |
exercises | array[5] | list of rows | Array of exercise objects with detailed information |
exercises.0.name | string | Barbell Ab Rollout | |
exercises.0.force | string | pull | |
exercises.0.level | string | intermediate | |
exercises.0.mechanic | string | compound | |
exercises.0.equipment | string | barbell | |
exercises.0.instructions | array | ["For this exercise you will need to get into a pushup position, but instead of having your hands of the floor, you will be grabbing on to an Olympic barbell (loaded with 5-10 lbs on each side) instead. This will be your starting position.","While keeping a slight arch on your back, lift your hips and roll the barbell towards your feet as you exhale. Tip: As you perform the movement, your glutes should be coming up, you should be keeping the abs tight and should maintain your back posture at all times. Also your arms should be staying perpendicular to the floor throughout the movement. If you don't, you will work out your shoulders and back more than the abs.","After a second contraction at the top, start to roll the barbell back forward to the starting position slowly as you inhale."] | |
exercises.0.muscle | string | biceps |
Failure modes
Errors come back as tool errors with a sentence the model can act on, not a bare status code.
| Status | What it means |
|---|---|
400 / 422 | The arguments didn't validate. The message names the offending one. |
401 | The OAuth session is invalid or expired — reconnect the server. |
403 | Out of credits. Not a bad key — the month's allowance is spent. |
404 | This skill isn't part of VerveKit. Check the catalog. |
429 | Brief rate limit. Retrying after a moment succeeds. |
Other ways to use Exercise Library Skill
Set up Exercise Library Skill on VerveKit, or reach the same source a different way. Your VerveKit account and credits work on all of them — one key, one balance.
Frequently asked questions
Do I have to tell the agent to use ExerciseLibrarySkill?
No. The tool's name and description are in the model's context once the server is connected, so it selects the tool when the question calls for it. Naming it explicitly works too and is useful when you want to force the call.
Does connecting the server expose every tool at once?
Yes — one connection lists the whole VerveKit catalog. Clients with a tool budget can usually filter the list; the credit cost is per call, so an unused tool costs nothing.
What does a call cost?
1 credit each time the tool actually runs. A model that reasons about the tool without calling it costs nothing.
Is there a REST version of this?
Yes — the same source is available as a plain HTTPS endpoint on APIVerve, linked above. Same data, same credits, same account.