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Read raw measurements

read_measurements

Read-onlyIdempotent

Retrieve raw individual health measurements, newest first, to show exact timestamps and sources instead of daily summaries. Filter by metric, source, or date range.

Instructions

Read individual measurement rows (not the daily_metrics aggregate), most recent first. Use this to see exactly when and where each reading came from, rather than just a day's summarized value.

Use this tool when:

the user wants raw/individual observations (e.g. "what measurements have I recorded?"), including their timestamp or source.

Do not use this tool when:

the user wants a broad, multi-metric overview -> use read_health_data instead.
the user wants one metric's day-by-day history -> use get_metric_history instead.
the user wants workout sessions -> use read_workout_sessions instead.

Privacy note: this server and its SQLite file are entirely local, but the data returned by this tool becomes part of the conversation sent to whatever model the calling client is configured with. If that model runs in the cloud rather than on your machine, treat this the same as pasting the data into a chat with that provider.

Input Schema

Name	Required	Description
`limit`	No	Maximum rows to return, 1 to 1000 (default 200).
`metric`	No	Only return this metric. Omit for all metrics.
`source`	No	Only return rows from this source, e.g. "Apple Watch". Omit for all sources.
`end_date`	No	Only return rows on/before this date (YYYY-MM-DD). Omit for no upper bound.
`start_date`	No	Only return rows on/after this date (YYYY-MM-DD). Omit for no lower bound.

Output Schema

Name	Required	Description	Default
`count`	Yes
`measurements`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.31Oct 20, 2026

changedInput schema / properties / limit / description

Previous value: -"Maximum rows to return (default 200)."New value: +"Maximum rows to return, 1 to 1000 (default 200)."

Changed2 schema fields changedv1.0.29Oct 3, 2026
- addedOutput schema / properties / measurements / items / properties / value / anyOf
```
Added value: +[
+  {
+    "type": "number"
+  },
+  {
+    "type": "null"
+  }
+]
```
- removedOutput schema / properties / measurements / items / properties / value / type
```
Removed value: -"number"
```
Addedv1.0.16Sep 15, 2026
Removedv1.0.15Sep 15, 2026
Addedv1.0.11Sep 13, 2026

TDQS

A4.4/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new context that annotations cannot express: default ordering (most recent first), the distinction from aggregated output, and a privacy note that returned rows become part of the model conversation. It omits pagination/truncation behavior, but the output schema likely covers the shape.

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

Conciseness4/5

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

Front-loaded with the core purpose, then cleanly segmented into when/when-not lists and a privacy note. Slightly long, and the privacy paragraph is the most verbose part, but each block earns its place by adding decision-relevant information.

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

Completeness5/5

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

For a read-only, 5-parameter, schema-rich tool with an output schema and full annotation coverage, this description supplies everything an agent needs: scope, routing to siblings, ordering, and a privacy caveat. No gaps remain that would cause a misselection or misinvocation.

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 100%, so all five parameters (limit, metric, source, start_date, end_date) are already documented with defaults and format hints. The description's mention of 'timestamp or source' loosely maps to the source/date params but adds no syntax or format detail beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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?

States a specific verb and resource ('Read individual measurement rows'), explicitly scopes it against the daily_metrics aggregate, and specifies ordering ('most recent first'). The contrast with the aggregate makes it immediately distinguishable from read_health_data and get_metric_history.

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

Usage Guidelines5/5

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

Provides explicit 'use when' conditions with an example query, plus a 'do not use when' list that names three alternatives (read_health_data, get_metric_history, read_workout_sessions) and the condition selecting each. Nothing is left to inference.

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