Call this before create_timestamp if you want to pre-check that the account can afford the operation and explain a likely 402 in advance, rather than reacting to one after the fact. Combine with get_pricing to compare balance against cost.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| data | No |
Changes observed during successful MCP inspections.
Output schema / (root)Previous value: -nullNew value: +{
+ "properties": {
+ "data": {
+ "properties": {
+ "credits": {
+ "description": "spArks balance.",
+ "type": "number"
+ },
+ "formatted": {
+ "example": "1,250.00",
+ "type": "string"
+ }
+ },
+ "type": "object"
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses that calling it helps pre-check affordability and explain 402 errors, which is useful behavioral context. However, it doesn't mention whether this is a read-only operation, if it requires authentication, or any rate limits. An output schema exists, so return format is covered elsewhere.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences that are front-loaded with the main use case. No wasted words, though it could be slightly more direct in stating what it returns.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the simplicity of a zero-parameter balance-check tool with an output schema, the description provides sufficient context about when and why to use it. It covers the key integration point with create_timestamp and get_pricing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool takes zero parameters, so there are no parameter semantics to describe. Baseline for zero params is 4, and the description appropriately focuses on usage context rather than nonexistent parameters.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description implies reading an account balance and frames it as a pre-check for affordability, which is a specific enough verb+resource. It doesn't explicitly state 'returns the account balance' but the intent is clear from context. It distinguishes itself from siblings by naming create_timestamp and get_pricing as related tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Explicitly states when to use this tool: before create_timestamp to pre-check affordability and explain a likely 402. It also recommends combining with get_pricing. However, it doesn't say when NOT to use it or provide alternative approaches.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.