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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds real value on top: it confirms it reads a confirmed transaction and discloses cost/rate limits ('25 free calls a day, then $0.01 USDC per call (x402)'). That pricing detail is exactly the kind of context an agent needs and annotations cannot 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?

Front-loads the key trigger and purpose, then adds outputs, an example, cost, and a doc pointer. Mostly efficient, though 'For failures it names the failing program and the fix' and 'why it failed' are somewhat 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?

For a read-only tool with fully documented params and no output schema, the definition covers purpose, trigger, return contents, cost, and a doc link. It is essentially complete, with only the sibling-relationship gap as a minor shortfall.

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 the schema already documents tx_id and network thoroughly (including the enum and 'never make one up'). The description only restates this with an example, adding little 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?

States a specific verb+resource: it explains a confirmed transaction, reporting outcome, fee, SOL/token changes, programs used, and failure reason. This is clearly distinguishable from generic readers, but it never names siblings like check_tx or why_failed, whose purpose appears to overlap with the 'why it failed' part.

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?

Gives an explicit trigger: 'Run after a transaction lands or fails... instead of guessing from logs.' That establishes when to reach for it. It stops short of stating when-not to use it or naming an alternative such as check_tx or why_failed.

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