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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds valuable context beyond that: 'Read-only public research data. No account access, no order placement or fund transfers. Not investment advice.' This reinforces the read-only nature and clarifies boundaries (no account access, no trading), which is useful for an agent deciding whether to call it. It does not contradict annotations.

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 extremely concise – four short sentences that front-load the core purpose (token scope), then give alternatives, then safety disclaimers. Every sentence earns its place, with no filler or redundancy.

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 5-parameter schema with 100% coverage and an output schema, the description covers essential usage context: it states the data scopes, points to alternatives, and clarifies the read-only, non-advice nature. It doesn't explain return format, but the output schema covers that. It also doesn't detail behavior like pagination or rate limits, but those aren't critical for a read-only research tool. Overall, it provides enough context for correct selection and invocation.

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%, so the schema already documents all parameters (chain, scope, token, upstream_raw_mode, include_upstream_raw). The description adds little beyond repeating scope names (holders, transfers, activity, smart_money) that are already in the scope property's description. It doesn't elaborate on param formats or defaults beyond what the schema provides, so the baseline 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 opens with 'Token scope' and enumerates the specific data types (holders, transfers, activity, smart_money), making it unambiguous what the tool returns. It also distinguishes itself by pointing to sibling tools for address-ledger and single-transaction queries, so an agent can tell it apart without opening the schema.

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?

Provides explicit alternates: 'Address ledger→get_address_transactions' and 'One tx→get_transaction'. This tells the agent when NOT to use this tool and which sibling to use instead. The 'Token scope' prefix clarifies that this is for token-level queries, not general on-chain address queries.

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