get_balance

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

With no annotations provided, the description carries the behavioral burden. It clearly discloses that only spendable/liquid coins are counted and explicitly calls out exclusions (staked SUI, DeFi positions), which is exactly the kind of non-obvious behavior an agent needs. It does not describe return format or unit handling, but the core behavioral ambiguity is well addressed.

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 compact, front-loaded with the primary action, and every sentence adds distinct value: the core function, the critical exclusions/nuance, and the sibling alternative. There is 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?

The description covers selection, semantics, and the main edge cases, which is strong for a 4-parameter tool. However, there is no output schema and the description does not specify the return unit or format of the balance value. This is a minor gap but still leaves some ambiguity for an agent invoking the tool.

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%, and the schema already documents owner, network, coin_type, and at_checkpoint, including defaults. The description adds the important 'liquid only' framing and the distinction from other tools, but it does not significantly expand on the individual parameters beyond what the schema provides. 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 uses a specific verb and resource: 'Get the liquid balance of one coin type for a Sui address'. It also notes the SUI default and the optional historical checkpoint, and clearly distinguishes itself from get_wallet_overview (all coins at once) and get_staking_summary/get_defi_positions (non-liquid holdings).

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 gives explicit when-to-use and when-not-to-use guidance. It states that staked SUI and DeFi value are excluded, advises pairing with get_staking_summary and get_defi_positions before drawing conclusions, and directs users to get_wallet_overview when every coin type is needed.

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