“Is there a Telegram API?” has an unhelpful answer: there are two, and the one most people mean cannot do the thing they want. It is worth separating them before choosing a tool.
Three routes, and what each one costs you
| Route | Credential | Can it read an arbitrary public channel? |
|---|---|---|
| Bot API | Bot token | No — only chats the bot belongs to. |
| MTProto client API | api_id + phone number | Yes, with an account that can be restricted. |
| Public web preview | None | Yes, for public channels with the preview on. |
The Bot API cannot read a channel it is not in
A bot receives updates from chats it is a member of. To read a channel, the bot has to be added to it as an administrator — which you can do to your own channel and cannot do to somebody else's. That single constraint rules the Bot API out for monitoring channels you do not own, which is the usual reason people go looking.
MTProto works, and puts an account at risk
The client protocol is what the real apps speak, and a client library using it can read any public channel and download its files. It needs an api_id and api_hash registered against a real phone number, and the account you sign in with becomes part of your infrastructure.
There is nothing improper about that. The problem is operational: the pipeline now has a credential that a person owns, that can be rate-limited, and whose restriction stops everything at once. Pipelines built this way tend to work well and then stop working entirely.
The web preview is public by construction
Every public channel is served at t.me/s/<handle> to anonymous visitors, which is how a channel link renders anywhere outside Telegram. It carries post text, timestamps, view counts, reactions, links and inline buttons.
Nothing about reading it can expire, because nothing about it was ever issued to you. That is the whole reliability argument, and it is the same one behind not requiring a SAM.gov key.
What the anonymous route genuinely costs
Private channels and groups are also out of reach, permanently and by definition. Passing one returns a free diagnostic row rather than a silent empty result.
When MTProto is the right choice anyway
Three cases: you need attachments, you need channels that are not public, or you need to act rather than read — sending, joining, replying. None of those is a scraping problem, and all of them justify holding an account. Reading public channels at scale is not one of them.
