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

With no annotations, the description carries the behavioral transparency burden. It discloses the sample window, the exact output categories, the trend, and the $0.01 per-call cost in USDC. It implies a read-only operation by saying 'returns,' but it does not explicitly state side-effect absence or failure behavior.

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?

Every sentence earns its place: purpose, returned data, usage directive, pricing, and parameter explanation. The most important information is front-loaded, and there is no redundant 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?

For a tool with a single optional parameter and no output schema, the description is complete. It covers all returned values, the lookback window, cost, recommended tiers, and parameter usage, so an agent has enough context to invoke it correctly.

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 description coverage is 0%, but the description fully compensates for the lone 'accounts' parameter by explaining that it is an optional list of writable account pubkeys and that omitting it yields a global sample. This gives the agent everything needed to use the parameter correctly.

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 what the tool does: it returns p50/p75/p90/p99 microlamports from the last 150 slots, the trend, and recommended fee tiers with SOL costs. However, it does not explicitly distinguish itself from sibling tools like simulate_transaction, so it stops short of full sibling differentiation.

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 gives a clear usage trigger: 'Use before every transaction you need to land.' It also explains how to handle the optional accounts parameter. It does not state when not to use the tool or name alternatives, so it is clear but lacks explicit exclusions.

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