Datai MCP Server

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

Annotations already provide readOnlyHint=true, destructiveHint=false, openWorldHint=true, and idempotentHint=true. The description adds valuable context beyond annotations by specifying what information is returned ('detailed information about all token holdings including amounts, USD values, and token metadata') and the purpose ('for portfolio analysis'), though it doesn't mention rate limits or authentication requirements.

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?

The description is efficiently structured in two sentences: the first states the core functionality, and the second elaborates on the returned data and purpose. Every sentence adds value without redundancy, and key information is front-loaded appropriately.

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 tool's moderate complexity (2 parameters, read-only operation), rich annotations, and 100% schema coverage, the description provides good contextual completeness. It explains what data is returned and the use case, though without an output schema, it could benefit from more detail on response format or pagination. The annotations cover safety and idempotency well.

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?

Schema description coverage is 100%, with both parameters well-documented in the schema. The description doesn't add any parameter-specific information beyond what's already in the schema (e.g., it doesn't clarify parameter interactions or provide examples). With complete schema coverage, the baseline score of 3 is appropriate.

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 clearly states the specific action ('Get token balances'), target resource ('for a wallet on a specific blockchain network'), and scope ('all token holdings including amounts, USD values, and token metadata'). It distinguishes itself from sibling tools like 'get_all_defi_positions' or 'get_defi_balances_by_chain' by focusing specifically on token balances rather than broader DeFi positions.

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?

The description implies usage context ('for portfolio analysis') but doesn't explicitly state when to use this tool versus alternatives like 'get_defi_balances_by_chain' or 'get_overall_balance_by_chain'. It mentions the specific blockchain requirement but doesn't provide guidance on tool selection among siblings.

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