tilwhen MCP server

• Registry namecom.tilwhen/tilwhenverified in the MCP registry

The registry name sits under tilwhen.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

• Stateanswerschecked 2026-10-21
• Tools9
• Server calls itselftilwhen
• Server version1.0.0
• Protocol version2025-06-18

On 2026-10-21 the server answered initialize and tools/list without a sign-in. First answer in 156 ms.

• Its tools do every use case we checked: count days remaining until a holiday or event; find the gap between two calendar dates.
• Checked on 4 of the 7 days it takes to judge reliability.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

• INITE MCP scoreafter a weeka score needs 7 daily checks: 4 so far
• What an agent can do with it2 of 2 use cases
• Answeredmeasuring4 of the 7 daily checks it takes to print a share
• Median first answer215 ms
• Space in an agent's context≈ 2,711 tokensthe definitions of all its tools (9), which an agent carries on every turn
• Tool definitionsA · 100 of 100
• Typed results9 of 9 toolsdeclared outputSchema: results come typed, read once

• Every tool passes all six checks.

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (30%), doing the product's job (25%), definitions (20%), context (10%) and use (15%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

• parse_date_query

  Parses queries like "90 business days from today in uganda" into a normalized operation, answers it, and returns the auditable receipt. Ambiguous dates (03/04/2027) return needsClarification instead of a guess.

• add_days

  The date N whole calendar days after a date (exclusive counting: the start date is day 0). Omit date for today in tz. For working days use business_days; for the gap between two dates use days_between.

• subtract_days

  The date N whole calendar days before a date (exclusive counting: the start date is day 0). Omit date for today in tz. For working days use business_days; for the gap between two dates use days_between.

• days_between

  Signed whole calendar days from the from date to the to date, midnight to midnight in tz: positive when to is later, negative when it is earlier. Endpoints are exclusive, so this is the gap and consecutive dates are 1 apart. Either date…

• business_days

  Span mode (from+to): business days between two dates, exclusive of the start day, inclusive of the end day. Add mode (days, optional date): the date N business days away. Passing from or to selects span mode and needs both; days and date…

• invoice_due

  Due date for Net-N payment terms (calendar days, invoice date = day 0). Optional roll-forward past weekends and, with a jurisdiction or custom calendar, public holidays.

• next_occurrence

  The next occurrence strictly after the base date (default today) of either a tracked event slug (e.g. "christmas") or a weekday (0 = Sunday .. 6 = Saturday). Provide exactly one of event/weekday.

• holidays

  Observed public holidays with the nominal (legal) date and status: rule (statutory) or declared (officially declared for that year). Declared-only holidays are omitted for undeclared years, with a holiday_data_incomplete warning.

• explain

  Runs any operation and returns the receipt plus human-readable derivation steps. Set op, then pass the fields that operation's own tool takes. Use it when the user asks how an answer was reached.