Retrieves the current Dexcom CGM glucose reading with trend arrow and reading age in minutes, enabling AI agents to check real-time glucose status in mg/dL or mmol/L.
Latest CGM glucose reading with trend arrow and how old it is (minutes).
units: "mg/dL" or "mmol/L" (defaults to DEXCOM_UNITS, else mg/dL).
| Name | Required | Description | Default |
|---|---|---|---|
| units | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the full burden. It does useful work by disclosing the return shape (reading, trend arrow, staleness in minutes) and the units default chain, but says nothing about what happens with no recent sensor data, data freshness limits, or auth requirements.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two tight, front-loaded segments: the capability first, then the units contract. Slightly hurt by the dangling quote and the stray leading newline in the units line, but no wasted sentences.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a single-parameter read tool with no output schema, the description covers payload contents and units adequately. It stops short of describing behavior when the sensor has no recent reading, which is the main failure mode an agent would need to anticipate.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 0% and the schema only declares an untyped nullable string, so the description must compensate — and it does, giving both allowed values ('mg/dL' or 'mmol/L') and the exact default resolution order (DEXCOM_UNITS, else mg/dL). Only minor gap is that it doesn't say whether an invalid value errors or falls back.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb+resource ('Latest CGM glucose reading') and names the payload ('trend arrow and how old it is'), so the agent knows exactly what comes back. It is clearly narrower than get_glucose and get_glucose_stats via the word 'Latest', but never names those siblings explicitly.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
'Latest' and the age-in-minutes output imply the tool is for current-state questions rather than historical ranges, which is usable context. However, there is no explicit when-to-use statement and no routing to get_glucose or get_glucose_stats for history or aggregates.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.