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Reject `subscriptions/listen` without `notifications`

Open Beginner friendly
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@subhashpolisetti is already working on this.

Since Oct 21, 2026.

  • #1208 by @subhashpolisetti — open

Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
68/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
java

Research direction

Start by locating SubscriptionsFeature and tracing how it parses subscriptions/listen parameters, then check nearby tests for malformed subscription requests. Add coverage for missing and null notifications being rejected while {} remains valid, and confirm the response is -32602 (and HTTP 400 where applicable).

Written by the indexing model from the issue text.

Description

area/server bug P2

Spec:

Current behavior

If notifications is missing or null, SubscriptionsFeature treats it as an empty filter, acknowledges the subscription and keeps an idle stream open.

Proposal

Answer with -32602 Invalid params (400 on HTTP), as for other malformed params. An explicit empty object {} stays valid.

Dominant language
Java
Stars
3.7k
Forks
1.2k
Avg merge
7h 34m
Merged PRs (30d)
46

Getting set up

First steps

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  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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