Skip to main content
Read-only actions. A company’s books as its adviser reads them. journal: the libro diario in date order; account lists an account’s ledger (libro mayor), each entry with only that account’s lines. trial_balance: the year’s sumas y saldos from 1 January to to, by account the opening balance, debit, credit and closing balance (debit positive); groups 6 and 7 start the year at zero and earlier results not yet applied show where the books reopened them (129 or 120); it leaves out the regularization, closing and reopening entries, so to 31 December (the default) gives the year’s results before the closing, and an earlier day drops that day’s ordinary entries; without prefix it groups by 4 digits, and at most 400 accounts are listed (accounts_omitted counts the rest: narrow with prefix). statements: the annual accounts in the PGC’s normal model (pérdidas y ganancias, balance) beside the year before; detail adds each line’s accounts. corporate_tax: the year’s Impuesto sobre Sociedades (modelo 200) from the books and the saved inputs, the 202 instalments it sets with their deadlines, and review codes to check; its rate’s kind is general (25 %), small_company (empresa de reducida dimensión: the year before’s turnover under 10 M€, art. 101 LIS: 24 % in 2025, 23 % in 2026), micro_company (under 1 M€) or new_entity (15 %). Each 202 instalment’s amount is what the company pays, by its method: 40.2 is 18 % of the last return’s cuota (on_last_return); 40.3 is the year’s base so far at period_rate, 5/7 of the year’s rate rounded down: 16 % for 23 %, 17 % for 24 % or 25 % (on_period_base), and is compulsory above 6 M€ of turnover (compulsory_period_base). Its version is the expected_version of corporate_tax_update and corporate_tax_filed. corporate_tax_update saves only the fields supplied and answers the recalculated tax; a year whose 200 was filed (filed) changes only with rectification, when the person asks to rectify that return. corporate_tax_filed records a 200 filed outside Melso (the day and the result filed, which must equal Melso’s calculation): the 202 instalments then build on the return filed (art. 40.2), whatever the year’s books or inputs say later. subaccounts lists the names the company gave its subaccounts (customers, suppliers, banks…) with their tax IDs, which the journal, the trial balance and the ledgers show; subaccount_set names one, adding or correcting it, and subaccount_delete forgets one: they move no amount. assets is the register of fixed assets: a purchase booked to an asset account is an asset by itself, depreciated straight-line from the day it entered service at a coefficient of the official table (art. 12.1.a LIS) on its cost less land and residual value, one entry a year; asset adds its table and entries; asset_preview shows the table a change would give without saving; asset_update changes how one is depreciated at expected_version (a year whose corporate tax was filed keeps what it booked); asset_create records an asset the imported books carry, with the depreciation they hold (opening); asset_dispose records the day one left the books, written off or sold by one of the company’s invoices, and asset_disposal_undo puts it back; asset_delete forgets an asset recorded from the books. entry_create prepares an editable manual proposal for what no document says (result application, an accrual, provision, stock count or correction): balanced lines, never VAT (472, 477), after imported books and outside locked periods or a year whose 200 was filed. entry reads a proposal by its id, or the source_id of its posted journal entry; entry_update changes an unposted proposal at expected_version and entry_delete removes an unposted proposal. A professional reviews and explicitly posts exact journal proposals in the app. VAT settlements, corporate tax and year-end closing also require explicit posting. Posted entries remain unchanged; corrections require explicit reversals and new postings in the app. Asset updates, disposal and deletion recalculate proposals and never replace posted history. opening_balance saves confirmed balances as one posted import up to its day (opening_balance_preview checks them first). Posted journals and opening balances cannot be deleted through book_imports; correct them through explicit reversals in the app. Amounts are EUR decimal strings. No action approves, files or pays a return. Each action accepts only its own fields (* required): journal(account, cursor, from, limit, to); trial_balance(year*, digits, prefix, to); statements(year*, detail); corporate_tax(year*); subaccounts(cursor, limit, prefix, q); assets; asset(id*); asset_preview(account, accumulated_account, acquired_on, concept, cost, depreciation_account, free_depreciation, id, in_service_on, land, name, opening, rate, residual); entry(id*); opening_balance_preview(date*, lines*). Availability: Empresa. Access: Live in the Melso app and over MCP for a signed-in person. Where the partner REST API covers the same area, that path is private beta until Melso enables your account. See Access and pricing. The live tool list is authoritative: the company’s plan and your role can narrow this contract. Understand access.

​
When to use

Use accounting_read for asset, asset_preview, assets, corporate_tax, entry, journal, opening_balance_preview, statements, subaccounts, trial_balance. Use accounting for the companion actions. The live tool list determines availability.

​
Input

​
Actions

The tool’s schema combines the fields of every action. Each action accepts only its own fields below; send action with them.

​
Read actions

These actions only read. They change nothing.
One asset as assets lists it, with its depreciation table year by year (amount, what the books hold of it so far, accumulated and net book value) and the sources of its entries (its purchase, each year’s depreciation, its write-off or the invoice that sold it), which journal does not filter by.
The table an asset would have with the fields given, without saving anything: an asset’s (id) or a new asset of the books (name, account, cost and acquired_on). Use it to show the person a change before asset_update.
The company’s register of fixed assets (inmovilizado), the most recently acquired first: a purchase booked to an asset account (source purchase) or an asset its imported books carry (source books). Each with its account, concept of the official table and coefficient (rate, rate_min, rate_max, percent a year), the day it was acquired and entered service, cost, land, residual value, the depreciation imported books hold for it (opening), what the books have depreciated by depreciated_through (the last month that has ended, or the day it left), its net book value, the year’s depreciation, its status (in_use, fully_depreciated, disposed), the day it left (disposal: write_off or sale, with its result), review codes to check and its version. totals add up the assets still in the books; concepts lists the official table (art. 12.1.a LIS); books_until is the last day the imported books cover.
The year’s corporate tax (Impuesto sobre Sociedades, modelo 200) as Melso calculates it from the books and the saved inputs: result before tax, adjustments, capitalization reserve available and applied, negative bases, taxable base, rate, cuota íntegra and líquida, withholdings, instalments paid and what is left to pay, deferred tax and the books’ charge; plus the 202 instalments that build on it, with deadlines. filed is the 200 filed for the year (null until it is recorded or Melso files it; differs when Melso’s calculation no longer gives it), and once it is there the instalments build on it (last_return_filed). deadline_passed: the 200’s deadline is over, so the year was most likely filed. review lists what to check. version is the expected_version for corporate_tax_update and corporate_tax_filed.
A manual entry proposal by its id, or the source_id of its posted journal entry: its day, concept, lines and version.
The company’s libro diario in date order: each entry’s number, kind (opening, normal, regularization, closing), source and lines with account, name, concept, debit and credit. account lists an account’s ledger (libro mayor): only the entries that move an account starting with those digits, each with only that account’s lines (other_lines counts the rest). A full page carries next_cursor.
Check an opening balance without saving it: the balances a company’s books carry at the end of date (debit or credit by account, together balanced; VAT and the year’s income and expenses included when the day is within a year), for a company whose earlier books are not imported. Answers what opening_balance would save, how many of Melso’s own entries it takes the place of (replaced) and what keeps it from being saved (problems).
The year’s annual accounts in the PGC’s normal model: the profit and loss account (cuenta de pérdidas y ganancias) and the balance sheet at the year’s end, each line keyed as the modelo 200 files it, beside the year before. detail adds the accounts behind each line.
The names the company gave its subaccounts (its customers, suppliers, banks, leasings…) in code order, each with its tax ID and source: import, from the list its accounting program exports, or manual. The journal, the trial balance and the ledgers name each subaccount so, before the name an imported journal carries. q finds a code by its first digits, or a name or tax ID by words; prefix keeps the subaccounts starting with it. total counts the matches; a full page carries next_cursor.
The year’s trial balance (balance de sumas y saldos) from 1 January to to: by account, the balance carried into the year, the year’s debit and credit and the balance at the end (debit positive, credit negative). Groups 6 and 7 start the year at zero; earlier results not yet applied show where the books reopened them (129 or 120). It leaves out the regularization, closing and reopening entries, so to 31 December (the default) gives the year’s results before the closing; an earlier day drops that day’s ordinary entries. Without prefix it groups by 4 digits; with prefix it shows the full subaccounts that start with it. At most 400 accounts are listed; accounts_omitted counts the rest.

​
Output

Read actions return the journal and ledgers, trial balance, annual accounts, corporate tax calculation, subaccounts, assets and their previews, or a saved journal proposal. Preview actions do not post entries. Use the action contract below and the returned schema for the selected result. The result uses MCP content blocks; JSON payloads are encoded in text and may also appear in structuredContent. Check isError before reading a success payload. When the server declares an outputSchema, it is reproduced below. Check the action result and its declared fields before reporting success.

​
Example

Use the actions of this tool in the order shown; its companion tool covers the other actions. These are the arguments of each call, in order.
1

Check the tax accounts in the trial balance

2

Read the corporate tax and note its version

The first call as a request. Use an OAuth access token issued for this MCP resource and replace the example identifiers with values from your own company.