Leave Hacker
REMOTE · LEAVEHACKER.APP
Which days of annual leave to book around bank holidays for the most days off, and cheap flights.
Available components
Last scanned (6 hours ago)
Scores higher than 78% of remote servers
Reachable. Last reached 6 Nov 2026.
Category Productivity and Notes
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Nothing on it is marked destructive, but we can't show that an anonymous caller can only read: full credit needs the server to list at least one tool and every tool to be verifiably read-only. We use a best-effort check of tool names and descriptions to tell read-only tools from tools that change things, so some genuinely read-only tools may not get full credit. Names that start with a read verb (get, list, read, search and similar) and accurate readOnlyHint annotations help. Meet that to earn full credit, or require authorisation. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability75
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 4252 tokens (~283/item across 15 items; 6 tools + 9 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management37
- Stability observed for 11 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 8 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
Checks we ran (13)
- TLS certificate
- Authorization
- HTTPS
- HSTS header
- DNSSEC
- Transport
- Schema quality
- Stability
- Tool coverage
- Injection markers
- Destructive annotations
- Judged manipulation
- MCP protocol
Does not apply to this hosted endpoint (2)
- Supply Chain SecurityScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
- Provenance & TransparencyScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
The score does not measure everything. What the score does not measure →
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 6 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 33 to 37. That category is still filling its 30-day observation window: 10 days of observed history at the previous scan, 11 at this one. The score rises as the window fills, whether or not the server changes.
- 5 Nov 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 4 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.
- 2 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.
- 30 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.
- 28 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.
- 27 Oct 26 0
- The server rewrote its instructions, which are the text every model session reads security
- Tool “find_trips” rewrote its description, which is the text the model reads security
- Schema quality: 173 → 241 ▼ functional
- Stability: unverified → 0.03 ▲ functional
- “best_days_to_book” added an optional parameter “next_working_day_off” cosmetic
- “best_days_to_book” added an optional parameter “us_holiday_ids” cosmetic
- “best_days_to_book” added an optional parameter “us_holidays” cosmetic
- “get_bank_holidays” added an optional parameter “next_working_day_off” cosmetic
- “plan_leave_year” added an optional parameter “next_working_day_off” cosmetic
- “plan_leave_year” added an optional parameter “us_holiday_ids” cosmetic
- “plan_leave_year” added an optional parameter “us_holidays” cosmetic
- “best_days_to_book” reworded the description of “region” cosmetic
- “get_bank_holidays” reworded the description of “region” cosmetic
- “leave_request_message” reworded the description of “region” cosmetic
- “plan_leave_year” reworded the description of “allowance” cosmetic
- “plan_leave_year” reworded the description of “region” cosmetic
- 26 Oct 26 74
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 6 Nov 2026 · Probed https://leavehacker.app/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=leavehacker.app | CN=YR1,O=Let's Encrypt,C=US | 25 Oct 2026 | 23 Jan 2027 | RSA 2048 | SHA256-RSA | 53be94bb5260ae8a0b89f766b476bdb97a1 |
| SANs: leavehacker.app | ||||||
| CN=YR1,O=Let's Encrypt,C=US (CA) | CN=Root YR,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | RSA 2048 | SHA256-RSA | a20253f15f2691c05dc1ce13b9bcca4e |
| CN=Root YR,O=ISRG,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | RSA 4096 | SHA256-RSA | f24b6d17f9d9ad7cb1c9fea78782699f |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of leavehacker.app. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | Trust anchor | 20326, 38696 | 8, 8 | Verified |
| app. | DS published | 23684 | 8 | Verified |
| leavehacker.app. | No DS | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://leavehacker.app/mcp | Verified | 200 | |
| http (plaintext) | http://leavehacker.app/mcp | HTTPS enforced | 308 | https://leavehacker.app/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
best_days_to_book Best days to book ~787
Find the days of annual leave to book around each public holiday (or cluster, such as Christmas and New Year) to get the most days off in a row: "book 4 days, get 10 off" options, cheapest first, with the exact dates. Use for "Which days should I book around Easter 2027 in Scotland?". Filter by holiday name (Easter, Christmas, Early May, Spring, Summer, St Patrick...). Past days are skipped. For parents in the UK, school: parent keeps leave inside the school holidays, using the council's published term dates when you pass council.
| Name | Type | Req | Description |
|---|---|---|---|
| council | string | – | With school: parent. The UK council whose term dates the school follows: its name ("Surrey", "Edinburgh"), its id ("surrey", "city-of-edinburgh") or the first half of a postcode ("GU1", "EH1"), looke… |
| from | string | – | Start of a date range, instead of year (yyyy-MM-dd). |
| holiday | string | – | Only holidays whose name contains this, e.g. "Easter", "Christmas", "May". |
| max_leave_days | integer | – | Most days of leave for one break. Default 9. |
| next_working_day_off | boolean | – | Ireland only: true if the person's employer gives the next working day off when a public holiday falls on a Saturday or Sunday (the civil service and banks do; Irish law doesn't require it, so the em… |
| region | string | – | Where the person works: england-and-wales, scotland or northern-ireland for UK bank holidays (from gov.uk); IE for Ireland; an Australian state or territory as AU-NSW, AU-VIC, AU-QLD, AU-WA, AU-SA, A… |
| school | string | – | none (default); parent: children at school, so leave is only booked in the school holidays. UK only. School staff can't book leave in term: use plan_leave_year with school: staff. |
| to | string | – | End of the date range, inclusive (yyyy-MM-dd). |
| us_holiday_ids | array | – | US only, with us_holidays: custom. Any of: new-years-day, mlk-day, washingtons-birthday, memorial-day, juneteenth, independence-day, labor-day, columbus-day, veterans-day, thanksgiving, day-after-tha… |
| us_holidays | string | – | US only: which holidays the person's employer gives. Private employers choose: common = the usual six (New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, Christmas); federal = a… |
| workdays | array | – | Days the person works, e.g. ["mon","tue","wed","thu"] for a four-day week. Defaults to Monday to Friday. |
| year | integer | – | Calendar year, e.g. 2027. Defaults to this year. |
| Name | Type | Req | Description |
|---|---|---|---|
| assumptions | string | yes | – |
| attribution | string | yes | Credit to show with the dates |
| council | – | yes | The council whose published dates are used, or null for typical dates |
| from | string | yes | – |
| licence | – | yes | – |
| maxLeaveDays | number | yes | – |
| notes | array | yes | – |
| opportunities | array | yes | – |
| region | string | yes | – |
| regionName | string | yes | – |
| school | string | yes | – |
| schoolYears | array | yes | Where each school year's dates come from |
| source | string | yes | – |
| sourceUrl | string | yes | – |
| to | string | yes | – |
| trainingDays | array | yes | The council's staff training (INSET) days: pupils are off, staff work |
| workdays | array | yes | – |
No examples provided.
find_trips Find cheap flights for a break ~242
Find the cheapest return flights from a departure airport that fit a break, one per destination, cheapest first, with booking links. Prices are cached airline fares in the departure country's currency (GBP, EUR, AUD or USD) and can change; if the result says sample, they are example prices only. Links go through leavehacker.app/go and are affiliate links: Leave Hacker may earn a commission if you book, at no extra cost to you. Say so when you share them. Use for "Find cheap flights from Manchester that fit the May bank holiday weekend" (work out the break's dates with best_days_to_book first).
| Name | Type | Req | Description |
|---|---|---|---|
| depart | string | yes | Outbound date, the first day of the break (yyyy-MM-dd). |
| limit | integer | – | How many destinations to return, up to 20. Default 10. |
| origin | string | yes | Departure airport or city IATA code, e.g. MAN (Manchester), LGW (Gatwick), EDI (Edinburgh), BHX, LON (all London airports). |
| return | string | yes | Return date, the last day of the break (yyyy-MM-dd). |
| Name | Type | Req | Description |
|---|---|---|---|
| affiliate | boolean | yes | – |
| currency | string | yes | ISO 4217: GBP from the UK, EUR from Ireland, AUD from Australia, USD from the US |
| depart | object | yes | – |
| disclosure | string | yes | – |
| fares | array | yes | – |
| origin | string | yes | – |
| priceNote | string | yes | – |
| return | object | yes | – |
| sample | boolean | yes | True: example prices, not real offers |
| searchAllUrl | string | yes | – |
No examples provided.
get_bank_holidays Bank holidays ~351
List the bank holidays (UK, from gov.uk) or public holidays (other countries, from Nager.Date) for a region in a year or between two dates, with weekdays and substitute days. Use it for questions like "When are the bank holidays in Scotland in 2027?". Ranges can be up to three years.
| Name | Type | Req | Description |
|---|---|---|---|
| from | string | – | Start of a date range, instead of year (yyyy-MM-dd). |
| next_working_day_off | boolean | – | Ireland only: true if the person's employer gives the next working day off when a public holiday falls on a Saturday or Sunday (the civil service and banks do; Irish law doesn't require it, so the em… |
| region | string | – | Where the person works: england-and-wales, scotland or northern-ireland for UK bank holidays (from gov.uk); IE for Ireland; an Australian state or territory as AU-NSW, AU-VIC, AU-QLD, AU-WA, AU-SA, A… |
| to | string | – | End of the date range, inclusive (yyyy-MM-dd). |
| year | integer | – | Calendar year, e.g. 2027. Defaults to this year. |
| Name | Type | Req | Description |
|---|---|---|---|
| attribution | string | yes | Credit to show with the dates |
| count | number | yes | – |
| from | string | yes | – |
| holidays | array | yes | – |
| licence | – | yes | – |
| notes | array | yes | – |
| region | string | yes | – |
| regionName | string | yes | – |
| source | string | yes | – |
| sourceUrl | string | yes | – |
| to | string | yes | – |
No examples provided.
get_school_holidays School holidays ~268
School holiday dates in the UK for a calendar year (half terms, Easter, summer, Christmas, and training days). With council, that council's published term dates, each school year with the council's source link and the date Leave Hacker last checked it; for a school year it hasn't published, and without a council, TYPICAL dates, which are the usual pattern and not official (Northern Ireland: the Department of Education's dates). Every holiday says which it is. Academies and independent schools can set their own, so tell the person to check their school's.
| Name | Type | Req | Description |
|---|---|---|---|
| council | string | – | The UK council whose term dates the school follows: its name ("Surrey", "Edinburgh"), its id ("surrey", "city-of-edinburgh") or the first half of a postcode ("GU1", "EH1"), looked up in Leave Hacker'… |
| region | string | – | UK nation: england-and-wales, scotland or northern-ireland. Defaults to england-and-wales, or to the council's nation when council is given. |
| year | integer | – | Calendar year, e.g. 2027. Defaults to this year. |
| Name | Type | Req | Description |
|---|---|---|---|
| caveat | string | yes | – |
| council | – | yes | The council whose published dates are used, or null for typical dates |
| notes | array | yes | – |
| region | string | yes | – |
| regionName | string | yes | – |
| schoolHolidays | array | yes | – |
| schoolYears | array | yes | Where each school year's dates come from |
| trainingDays | array | yes | The council's staff training (INSET) days: pupils are off, staff work |
| typical | boolean | yes | True when every date here is typical, not published |
| year | number | yes | – |
No examples provided.
leave_request_message Leave request message ~251
Write the short, polite message asking a manager for the leave days of a break, in the same words as the Leave Hacker app. Pass the dates to book; the break's first and last day are worked out from the weekends (and bank holidays, if you pass region) either side unless you pass them.
| Name | Type | Req | Description |
|---|---|---|---|
| break_end | string | – | Last day off, if known (yyyy-MM-dd). |
| break_start | string | – | First day off, if known (yyyy-MM-dd). |
| dates_to_book | array | yes | The working days to book as leave (yyyy-MM-dd). |
| region | string | – | Optional, to count bank holidays next to the dates: england-and-wales, scotland or northern-ireland for UK bank holidays (from gov.uk); IE for Ireland; an Australian state or territory as AU-NSW, AU-… |
| Name | Type | Req | Description |
|---|---|---|---|
| break | object | yes | – |
| datesToBook | array | yes | – |
| message | string | yes | – |
| notes | array | yes | – |
No examples provided.
plan_leave_year Plan a leave year ~942
Plan a whole leave year: the set of breaks that turns the person's annual leave allowance into the most days off, using every bank holiday, with the dates to book for each break and the totals. Handles any leave year start date, part-time working days, three plan styles and school holidays (parents: breaks only in school holidays; school staff: the holidays themselves), from the council's published term dates when you pass council and typical dates otherwise. Use for "Plan my 28 days of leave for 2027, I have kids at school in Leeds".
| Name | Type | Req | Description |
|---|---|---|---|
| allowance | integer | – | Days of annual leave (PTO in the US) a year, not counting public holidays. Defaults to the usual for the region: 25 in the UK, 20 in Ireland and Australia (the legal minimum for full-time work), 15 i… |
| council | string | – | With school: parent or staff. The UK council whose term dates the school follows: its name ("Surrey", "Edinburgh"), its id ("surrey", "city-of-edinburgh") or the first half of a postcode ("GU1", "EH1… |
| days_used | integer | – | Days of this leave year's allowance already taken or booked. Default 0. |
| leave_year_start_day | integer | – | Day of the month the leave year starts. Default 1. |
| leave_year_start_month | integer | – | Month the leave year starts, 1–12 (1 = January, 4 = April). Default 1. |
| leave_year_starting | integer | – | Instead of year: the calendar year the leave year starts in, e.g. 2027 for January–December 2027 or April 2027–March 2028. |
| next_working_day_off | boolean | – | Ireland only: true if the person's employer gives the next working day off when a public holiday falls on a Saturday or Sunday (the civil service and banks do; Irish law doesn't require it, so the em… |
| region | string | – | Where the person works: england-and-wales, scotland or northern-ireland for UK bank holidays (from gov.uk); IE for Ireland; an Australian state or territory as AU-NSW, AU-VIC, AU-QLD, AU-WA, AU-SA, A… |
| school | string | – | none (default); parent: children at school, so breaks only in the school holidays; staff: works in a school, so the school holidays are the breaks. UK only. |
| style | string | – | mix: two proper holidays of 9+ days, the rest long weekends (default). longWeekends: as many 3–5 day weekends as possible. bigTrips: fewer trips of 9+ days. |
| us_holiday_ids | array | – | US only, with us_holidays: custom. Any of: new-years-day, mlk-day, washingtons-birthday, memorial-day, juneteenth, independence-day, labor-day, columbus-day, veterans-day, thanksgiving, day-after-tha… |
| us_holidays | string | – | US only: which holidays the person's employer gives. Private employers choose: common = the usual six (New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, Christmas); federal = a… |
| workdays | array | – | Days the person works, e.g. ["mon","tue","wed","thu"] for a four-day week. Defaults to Monday to Friday. |
| year | string | – | Which leave year: current or next. Defaults to current, or next when under 90 days are left. |
| Name | Type | Req | Description |
|---|---|---|---|
| allowance | number | yes | – |
| assumptions | string | yes | – |
| attribution | string | yes | Credit to show with the dates |
| bankHolidays | array | yes | – |
| breaks | array | yes | – |
| budget | number | yes | – |
| council | – | yes | The council whose published dates are used, or null for typical dates |
| daysUsed | number | yes | – |
| leaveYear | object | yes | – |
| licence | – | yes | – |
| notes | array | yes | – |
| plannedFrom | string | yes | – |
| region | string | yes | – |
| regionName | string | yes | – |
| school | string | yes | – |
| schoolHolidays | array | yes | – |
| schoolYears | array | yes | Where each school year's dates come from |
| source | string | yes | – |
| sourceUrl | string | yes | – |
| style | string | yes | – |
| totals | object | yes | – |
| trainingDays | array | yes | The council's staff training (INSET) days: pupils are off, staff work |
| workdays | array | yes | – |
No examples provided.
How do I install the Leave Hacker MCP server?
Leave Hacker is a hosted endpoint at https://leavehacker.app/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · leavehacker.app
claude mcp add --transport http app-leavehacker-leave-hacker 'https://leavehacker.app/mcp'
What is the Leave Hacker MCP server?
Leave Hacker is an MCP server listed in the public MCP registry as app.leavehacker/leave-hacker. Which days of annual leave to book around bank holidays for the most days off, and cheap flights. This page covers its hosted endpoint (https://leavehacker.app/mcp).
Is the Leave Hacker MCP server safe to use?
Leave Hacker scores 79 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the Leave Hacker MCP server expose?
Leave Hacker exposes 6 tools: get_bank_holidays, best_days_to_book, plan_leave_year, get_school_holidays, find_trips, leave_request_message. Their descriptions and schemas cost roughly 2,841 tokens of context every time the server is loaded.
Does the Leave Hacker MCP server require authentication?
No. We connected to Leave Hacker without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Leave Hacker MCP server still maintained?
Leave Hacker is still listed as active in the MCP registry. We last reached this channel on 6 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What did VerifyMCP test on the Leave Hacker MCP server?
VerifyMCP ran 13 checks on Leave Hacker, covering TLS certificate, Authorization, HTTPS, HSTS header and 9 more. Supply Chain Security and Provenance & Transparency do not apply to a hosted endpoint, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.