> **Components:** Strava MCP connector (`list_activities`), Claude (claude-sonnet-5)
>
> **Athlete:** [Daniel Griffin on Strava](https://www.strava.com/athletes/6631112) · [UltraSignup results](https://ultrasignup.com/m_results_participant.aspx?fname=Daniel&lname=Griffin)
>
> **Date observed:** 2026-09-18
>
> **Severity:** Moderate. The user got a wrong assessment of their fitness history, stated with confidence.
>
> **Status:** Reported for discussion. This report doesn't claim a root cause.

## User intent

The user asked for a marathon training plan based on their actual training
history. They are a former ultramarathon runner returning to training, and
wanted a plan that accounted for their long-term base rather than only their
recent weeks.

## What happened

1. The assistant retrieved activities since 2026-06-01. It found a longest
   recent run of about 5 miles and advised against a 10-week marathon build.
2. The user asked: *"But you see my historical base?"*
3. The assistant retrieved the 100 most recent activities, back to 2023-06-16.
   The response included `has_next_page: true`. The assistant reported:
   *"Longest run ever logged: ~9.5 miles"* and *"he's never built
   marathon-distance mileage."*
4. The user pasted race results from UltraSignup, including a 200-mile finish
   in 2017.
5. The assistant said those races predated the Strava account.
6. A later date-filtered query (2015–2018) returned the 2017 data from the same
   account, including an activity titled *"Recovery Run from Bigfoot 200."*

## Expected behavior

The assistant should understand the scope of the training data it has retrieved
and keep its claims within that scope. If the available data cannot support a
conclusion about the user's full history, it should make that uncertainty
explicit.

## Friction observed

**In the connector**

- The tool description says nothing about how much of the history one call
  returns, or how to reach the rest.
- A call with no arguments returns the 30 most recent activities.
- Responses don't include a total activity count or the date of the oldest
  activity. The only sign that more data exists is `has_next_page`.
- There's no single tool for retrieving the full history.
- Strava's launch announcement promises access to users' "full training
  history." The help documentation says nothing about date ranges or
  pagination.

**In the conversation**

- The assistant didn't tell the user which date range each query covered.
- It stated conclusions about the user's whole history ("ever," "never") after
  retrieving only part of it.
- It gave a reason for the missing data (that the account didn't exist yet)
  without checking it.
- The pasted race results ran two fields together, so division place and
  finish time appeared as one string. The assistant read them without
  separating them and reported a 200-mile time of 46:20. The actual time was
  96:20:18.

## Notes

- The connector's date filters and pagination worked correctly when used.
- Searching for similar public reports found none. The connector began rolling
  out the week of June 1, 2026.