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Specification API·101

API · APIs & Integrations Defined scope Fixed fee

REST API Design and Documentation

API design and OpenAPI documentation with a mock server, so partners and front-end teams can integrate without waiting on you.

Fee · GST incl.
₹18,999
Duration
9 working days
Deliverables
7

01 Overview

When an API is undocumented, every partner integration starts with guesswork and a chain of emails. We produce a written contract for your API, either designed from requirements or documented from the endpoints you already run, with consistent naming, pagination and filtering, errors that identify the failing field, and a versioning scheme that allows change without breakage. The OpenAPI specification is published with an interactive console and a generated mock server, so outside developers can build and test their side before your implementation is finished.

02 Deliverables

7 items

What you receive at handover

  1. D01 OpenAPI 3 specification for up to 40 endpoints
  2. D02 Agreed conventions for pagination, filtering, sorting and error responses
  3. D03 Hosted documentation site with example requests and responses
  4. D04 Mock server built from the specification so partners can test early
  5. D05 Authentication guide explaining keys, tokens and rate limits
  6. D06 Written versioning and deprecation policy
  7. D07 Postman collection for your partners and support staff

03 Outcomes

What should be true once it ships

  • Partners integrate from the documentation instead of a run of clarifying emails
  • Front-end work begins against the mock server rather than waiting for the back end
  • Breaking changes are scheduled under a published policy instead of discovered in production

04 Process

How the 4 stages run

  1. Review We inspect your existing endpoints, or gather requirements for a new API
  2. Design Resources, conventions and the error model are agreed with your engineers
  3. Specify The OpenAPI document is written, examples added and the mock server generated
  4. Publish The documentation goes live and we walk your team through it

05 Fit & inputs

A good fit for

  • Teams whose API reference currently lives in a spreadsheet
  • Products about to open integrations to partners or customers
  • Front-end and back-end teams that keep disagreeing about payload shapes

What we need from you

  • Codebase access, or a list of your existing endpoints
  • An engineer available for two design discussions
  • Partner requirements or contract terms that constrain the interface

These inputs are collected through the technical brief in your dashboard after payment. The duration is counted from when they arrive.

06 Answers

Questions about this engagement

Yes. Reading an unfamiliar codebase and turning it into a written contract is central to this engagement.

Implementation is not included. Where we find small inconsistencies, we can correct them with your agreement.

Yes. You receive the equivalent: a schema, documentation and example queries, for the same fee.

This is technology work delivered digitally — nothing is shipped. Work is delivered into systems you control within the duration stated above, and the delivery and refund policies set out what happens if a date is missed.

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