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

Annotations already declare a non-readonly, non-idempotent, non-destructive write; the description goes beyond by clarifying it BUILDS an unsigned transaction (not execute) and that approval must precede it. That unsigned-vs-executed distinction and the approval dependency are meaningful behavioral context the annotations wouldn't convey.

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?

Three sentences, front-loaded with the action, then mechanics, then prerequisite, then a pointer to related reads. No filler; every clause carries actionable information.

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?

An output schema exists (so return shape needn't be explained) and annotations cover the safety profile; the description supplies the approval prerequisite and yield-check follow-up. Slightly short of 5 only because the unsigned-transaction handoff workflow (sign/send via dev_send?) isn't stated.

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%, so baseline is 3; the description earns extra by explaining that assets are the pool's underlying (USDC/WETH/cbBTC) and that receiver receives minted tranche shares, adding intent beyond the raw field descriptions.

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?

Precise verb+resource: 'Build an unsigned deposit transaction into an Arcadia lending tranche (ERC-4626)' and explains the lender mechanics (deposit underlying, receive interest-accruing shares). It doesn't explicitly contrast with write_pool_redeem, but it does route to adjacent siblings (write_wallet_approve, read_pool_list/read_pool_info), so differentiation is implied rather than spelled out.

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?

States a concrete prerequisite ('Requires prior ERC-20 approval to the tranche (see write_wallet_approve)') and points to read_pool_list/read_pool_info for yield checks. Clear usage context, though it never says when NOT to use it or explicitly names write_pool_redeem as the inverse operation.

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