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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely useful behavioral context: it explains the protocol-level privacy constraint and states it reports shielded *shape* (counts) rather than guessing. It stops short of richer operational detail (e.g., behavior for unconfirmed/unknown txids), so a solid 3.

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?

Front-loaded with purpose, then clearly delimited 'When to use', 'Do not use', and 'Returns' segments, so an agent can scan it quickly. It is dense and the Returns enumeration is long, but with no output schema that enumeration earns its place rather than being redundant.

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?

No output schema exists, and the description compensates by listing the full return shape (found, confirmations, block fields, size, transparent and shielded breakdowns, not_disclosed_by_protocol[]). Combined with annotations and a fully documented single parameter, an agent has everything needed to call and interpret this 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 coverage is 100% with a single documented txid parameter ('64 hex char Zcash transaction id'), so the schema carries the load. The description adds no format or validation meaning beyond what the schema already states, making the baseline 3 correct.

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?

States a specific verb and resource ('Zcash transaction check by txid') and scopes it to a named source ('our own Zebra node'), then enumerates the exact facts returned (confirmations, block height/time, active-chain status, size, transparent vs shielded split). This clearly distinguishes it from the many sibling *_get_transaction tools across BTC, ETH, TRON, and XMR.

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?

Explicit 'When to use' (did a ZEC payment land, how deep is it, does it involve shielded components) and explicit 'Do not use' (learning shielded amounts or parties, which the protocol hides and only a viewing key can reveal). The exclusion is paired with the alternative behavior the tool offers instead, leaving nothing to inference.

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