midl_get_rune_balance

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, signaling a safe read operation. The description adds behavioral context by explaining the address fallback behavior, which is beyond the annotations. No contradictions.

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 front-load the key information: action (get balance), target (specific Rune), and condition (address fallback). No wasted words.

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?

For a simple read-only tool with two parameters, the description and schema together provide sufficient context. An output schema is absent, but the return value (balance) is obvious. Minor improvement could mention the unit or format, but not essential.

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 coverage is 100% with both parameters described (address optional, runeId required with pattern). The tool description repeats the address fallback but adds no new semantics. With high coverage, 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 clearly states the tool retrieves the balance of a specific Rune, with a fallback to the connected wallet's ordinals address if no address is provided. It distinguishes itself from sibling tools like 'midl_transfer_rune' (write) and 'midl_get_runes' (list runes).

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 when to use this tool: to query a specific Rune's balance. While it doesn't explicitly state when not to use it, the sibling names provide sufficient context (e.g., 'midl_transfer_rune' for transfers). No exclusions or alternatives are mentioned, but the purpose is clear.

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