Fluxmail

Read email body

get_email_body

Read-only

Read a bounded portion of an email body; use the returned nextOffset to continue fetching the rest when the message exceeds your character limit.

Instructions

Read a bounded portion of one email body. Use nextOffset to continue.

Input Schema

Name	Required	Description
`format`	Yes
`offset`	No
`maxChars`	No
`accountId`	No	Account to operate on. Optional when exactly one account is connected.
`messageId`	Yes

Output Schema

Name	Required	Description	Default
`data`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv0.19.0Oct 30, 2026

changedInput schema / properties / accountId / anyOf

Previous value: -[
-  {
-    "minLength": 1,
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maxLength": 512,
+    "minLength": 1,
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / messageId / maxLength
```
Added value: +512
```

Changed10 schema fields changedv0.15.0Oct 17, 2026
- addedInput schema / properties / accountId / anyOf
```
Added value: +[
+  {
+    "minLength": 1,
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]
```
- removedInput schema / properties / accountId / minLength
```
Removed value: -1
```
- removedInput schema / properties / accountId / type
```
Removed value: -"string"
```
- addedInput schema / properties / maxChars / anyOf
```
Added value: +[
+  {
+    "maximum": 50000,
+    "minimum": 1,
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  }
+]
```
- removedInput schema / properties / maxChars / maximum
```
Removed value: -50000
```
- removedInput schema / properties / maxChars / minimum
```
Removed value: -1
```
- removedInput schema / properties / maxChars / type
```
Removed value: -"integer"
```
- addedInput schema / properties / offset / anyOf
```
Added value: +[
+  {
+    "minimum": 0,
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  }
+]
```
- removedInput schema / properties / offset / minimum
```
Removed value: -0
```
- removedInput schema / properties / offset / type
```
Removed value: -"integer"
```
Changed1 schema field changedv0.11.1Oct 1, 2026
- removedOutput schema / $schema
```
Removed value: -"http://json-schema.org/draft-07/schema#"
```
Addedv0.11.0Sep 26, 2026

TDQS

B3.2/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful context that reads are bounded and must be continued via offsets, but it omits default/max page size and behavior at end of content.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, front-loaded with the core action, with zero filler. Slightly penalized because the pagination pointer references a nonexistent parameter name.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be described. Still, for a 5-parameter tool with only 20% schema coverage, the description leaves format selection, offsets, and limits unclear enough to hinder correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 20% (only accountId is documented), so the description should carry the load but mostly doesn't. Worse, it cites 'nextOffset', which is not an actual parameter name (the schema exposes 'offset'), risking agent confusion, and it never clarifies the required 'format' enum values or what 'maxChars' bounds.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Read') and resource ('email body') and clarifies the read is partial/bounded. However, it does not explicitly distinguish itself from the sibling get_email, so an agent must infer that get_email returns the full message while this returns a page of the body.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives pagination guidance ('Use nextOffset to continue'), which implies this is the right tool for fetching a body incrementally. It offers no when-to-use guidance relative to get_email/get_thread, and no prerequisites are mentioned.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.