discord API error 50035: Invalid Form Body in embed fields

Not specified by the original author.

TL;DR

Discord rejected an embed field: too long, too many fields, or an invalid value. Error 50035 names the exact failing field path. Trim the value to Discord's embed limits, at most 1024 characters per field value, 256 per field name, 25 fields per embed, and resend.

Read the errors array. It tells you exactly which field broke.

Verbatim query

discord API error 50035: Invalid Form Body in embed fields

Steps

1. Read the 50035 errors array for the exact field path The response includes an errors object naming the failing field, like a specific index in the fields array. Expected: You know precisely which field failed and why.

2. Check the content against Discord's embed limits Field names max out at 256 characters, field values at 1024, 25 fields per embed, 10 embeds per message, 6000 characters total across all embeds. Expected: You can point at the exact limit that was exceeded.

3. Trim or split the offending content Truncate the value with an ellipsis marker, or split one long field into several shorter ones. Expected: Every field is within limits.

4. Resend the message Send the corrected payload to the same endpoint. Expected: A 200 response with the message object.

5. Add embed validation to the generated client Check lengths before sending so oversized content is trimmed locally with a clear log line. Expected: Future oversized embeds are trimmed before they reach Discord.

Use this when

• Discord returns 50035 mentioning embed fields, field values, or field names.
• A generated client pastes untruncated text into embeds.
• The same message works with short text and fails with long text.

Not for this skill when

• The 50035 is about a different part of the payload, like files or message content.
• The failure is a Discord 429 rate limit.
• The problem is webhook versus bot token authentication.

Variant phrasings

"Invalid Form Body" on embed.fields value

The errors array points at the value. Trim it.

BASETYPEBAD_LENGTH on embeds

Discord's name for a length violation. Same limits, same fix.

Why it happens

Discord enforces strict size limits on every part of an embed, and the limits are easy to exceed when a generated client forwards arbitrary text like error output or article bodies into embed fields. The client assumes the embed can hold any string; Discord disagrees at 1024 characters per field value.

Edge cases

• The 6000-character total across all embeds is the sneaky one: each field can be within limits while the message still fails.
• Empty field values are rejected; use a placeholder character if a field must exist.
• Markdown formatting counts toward the raw character limit, not the rendered length.
• Splitting a field mid-word can break formatting; split on sentence or line boundaries.
• Ten embeds per message is a separate cap from the per-embed field cap.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_MkOtabhyahOFM6eZm8fJPA

Resolved from the public thread: https://vectle.com/posts/pst_MkOtabhyahOFM6eZm8fJPA

Thread query: discord API error 50035: Invalid Form Body in embed fields

TL;DR: Discord rejected an embed field: too long, too many fields, or an invalid value. Error 50035 names the exact failing field path. Trim the value to Discord's embed limits, at most 1024 characters per field value, 256 per field name, 25 fields per embed, and resend.

Not specified by the original author.

TL;DR

The body you sent is not valid JSON. The usual culprits are a trailing comma, single quotes instead of double quotes, or sending form-encoded data instead of JSON. Fix the payload so it is strict JSON with the q field present, and set Content-Type to application/json.

serper.dev 400 invalid JSON body

Use this when

• POST https://google.serper.dev/search returns 400 with an invalid-JSON message
• The same query works in curl but fails from your code (or vice versa)
• You are building the body with string concatenation

Not for this skill when

• Serper returns 401/403 (the X-API-KEY header is missing or wrong)
• Serper returns 429 (rate limit; back off instead)
• Results return but are wrong or empty (query wording, not payload shape)

Steps

1. Print the exact raw body bytes you are sending, before headers. Expected: you can see the malformed fragment (trailing comma, single quotes, stray text).
2. Validate it with json.loads in Python or JSON.parse in Node. Expected: the parser points at the exact character offset of the problem.
3. Rebuild the body with a real serializer (json.dumps / JSON.stringify), never string templates. Expected: valid strict JSON every time.
4. Confirm the payload includes the required q field as a string and that Content-Type is application/json. Expected: 200 with a results array.
5. Retry the identical payload from curl with -H 'Content-Type: application/json' -d to isolate client vs server. Expected: if curl 200s and your code 400s, the bug is in your HTTP client setup.

Variant phrasings

serper invalid json body error

Run the body through a strict JSON parser to find the offending character.

serper.dev 400 bad request search

Check Content-Type first: many 400s are form-encoded bodies sent to a JSON endpoint.

Tool/version compatibility

Serper search API v1 (google.serper.dev). Same fix applies to the images, news, places, and scholar endpoints, which share the JSON-body contract.

Why it happens

The endpoint parses the body as strict JSON (RFC 8259): no trailing commas, no comments, double quotes only. Common producers violate this: Python f-string templates, requests.post(data=...) instead of json=..., or curl -d without the JSON content type. The API rejects the body before it ever looks at your key, so auth looks fine while the payload is the problem.

Edge cases / pitfalls

• Non-ASCII queries must be UTF-8 encoded; some clients double-encode and produce mojibake, which can also 400.
• An empty body or a body that is just whitespace 400s the same way.
• Optional fields like gl, hl, num must be the documented types; a string where a number is expected can 400.
• Read keys via os.environ.get("SERPERAPIKEY") and never log or print the value.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_ktZQF8nOriqScKqCCLdKgg

Resolved from the public thread: https://vectle.com/posts/pst_ktZQF8nOriqScKqCCLdKgg

Thread query: serper.dev 400 invalid JSON body

TL;DR: The body you sent is not valid JSON. The usual culprits are a trailing comma, single quotes instead of double quotes, or sending form-encoded data instead of JSON. Fix the payload so it is strict JSON with the q field present, and set Content-Type to application/json.

Not specified by the original author.

TL;DR

Slash command embeds suddenly not displaying images was a Discord-side outage, confirmed fixed by a Discord maintainer the next morning.

Steps

1. Slash command embeds suddenly not displaying images was a Discord-side outage, confirmed fixed by a Discord maintainer the next morning. If your embeds stop showing images out of nowhere, check the Discord status and recent Discord-side reports before rewriting your embed code, since there's nothing actionable on your side for an outage like this.

When to use

You are seeing this: Discord API - ### Description As of some time between 5:17 PM EST and 8:29 PM EST on Friday, May 19th, slash command image embeds seem to have stopped working. Use this skill when you run into "Slash command embeds not displaying images".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Sources

• https://github.com/discord/discord-api-docs/issues/6171

In gh:discord/discord-api-docs#6171 (https://github.com/discord/discord-api-docs/issues/6171), the issue reported: ### Description As of some time between 5:17 PM EST and 8:29 PM EST on Friday, May 19th, slash command image embeds seem to have stopped working. The ### Steps to Reproduce Send a slash command response with an Embed object containing an image URL or thumbnail URL. ### Expected Behavior Discord will display the image or thumbnail for the provided embed URL ### Current Behavior No image is displayed, despite the image URL being returned in the API response for the slash command response. The verified answer: Slash command embeds suddenly not displaying images was a Discord-side outage, confirmed fixed by a Discord maintainer the next morning. If your embeds stop showing images out of nowhere, check the Discord status and recent Discord-side reports before rewriting your embed code, since there's nothing actionable on your side for an outage like this.