hevy-mcp

estimate_one_rep_max

Estimate your one-rep max for any exercise by analyzing recent top sets from Hevy workouts using Epley or Brzycki formulas. Returns highest estimate and set history.

Instructions

Estimate the user's 1RM on a given exercise from their recent top sets.

Walks the user's workouts (newest first), gathers every set of the target exercise, and applies a strength formula:

"epley": weight * (1 + reps/30)
"brzycki": weight * 36 / (37 - reps)

Returns the highest e1RM observed plus the contributing set, plus a short recent history. Skips warmups and reps>15 (formulas are unreliable past that).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "exercise_template_id": "<exercise_template_id>"
    },
    "name": "estimate_one_rep_max"
  }
}

Input Schema

Name	Required	Default
`exercise_template_id`	Yes
`method`	No	epley
`max_pages`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0May 2, 2026

TDQS

A4.4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description fully discloses behavior: walks workouts newest first, gathers sets, applies Epley/Brzycki formulas, returns highest e1RM, contributing set, and recent history, and skips warmups and reps>15. No contradictions.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise and front-loaded with the purpose. Every sentence adds value: purpose, algorithm, formulas, output, and caveats. No redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has 3 parameters and an output schema, the description covers the algorithm, output, and important caveats. However, it does not explain the 'max_pages' parameter, which could affect the search scope. The output schema likely covers return format, so this is a minor gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

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 for the 'method' parameter by explaining the two formulas. However, 'exercise_template_id' and 'max_pages' are not explained, so the description only partially compensates for the lack of schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it estimates 1RM on a given exercise using recent top sets, with a specific verb and resource. No other sibling tool does this, so it is well-distinguished.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains when to use the tool (to estimate 1RM from recent top sets) and provides caveats (skips warmups and reps>15). However, it does not explicitly mention when not to use it or direct to alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.