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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuine context beyond that with ordering ('newest first') and the hash-chained nature of entries, but says nothing about pagination, default page size, or how 'limit' bounds the result.

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?

A single short sentence, front-loaded with the resource and immediately followed by the two properties that matter most (ordering and hash-chaining). No filler.

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?

There is no output schema, so the description should carry the return-value burden; it partially does by saying entries come newest-first and are hash-chained. However, it omits pagination behavior, the meaning/default of 'limit', and what an entry actually contains, which leaves real gaps for a list 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 only 50%: 'api_key' is documented in the schema, but 'limit' has no description anywhere. The description does not mention limit, its default, or its maximum, so it fails to compensate for the coverage gap.

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?

Names the resource ('ledger entries') and adds two distinguishing traits: ordering ('newest first') and integrity ('hash-chained'). It never uses an explicit verb like 'list', and it does not explicitly differentiate from nearby siblings such as balance or my_credits, so it is clear but not sibling-routing.

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?

No when-to-use guidance at all. With siblings like balance, my_credits, and my_rewards in the same credit domain, the description gives the agent no signal for choosing ledger over them.

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