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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and non-destructive, so the safety profile is covered. The description still adds real operational context beyond that: statelessness, a 32 KB payload cap, 60 RPM rate limit, demo mode or x402 payment of 10 sats, and an HTTP 400 on invalid input. However, it never says what 'optimal' means or which chain/endpoint is actually called, so it is good rather than exemplary.

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?

Purpose is front-loaded in the first sentence, usage and exclusion in the second, operational constraints last — a logical order with no filler. The final clause is a run-on cramming statelessness, size cap, rate limit, payment modes and error code into one sentence, which costs some readability.

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?

With an output schema present, return values need not be described, and the description covers rate limits, size limits, payment/auth paths and failure behavior for a read-only edge call. The one substantive gap is the tx_type default mismatch and the unspecified definition of 'optimal' estimation.

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 both enums documented, so the baseline would be 3. But the description asserts 'tx_type' defaults to 'simple_transfer', while the schema explicitly says it defaults to 'dex_swap' when omitted — the description actively introduces conflicting parameter semantics rather than merely restating them.

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 ('Calculates ... compute-unit microlamport priority fees and Jito bundle tip lamports') plus the objective (target block-inclusion probability). It also explicitly distinguishes itself from the nearest sibling, estimate_bitcoin_mempool_fees, so an agent can route without opening either schema.

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 use condition ('when setting SetComputeUnitPrice and Jito tips before broadcasting a Solana transaction') and an explicit when-not with the named alternative ('for querying Bitcoin L1 sat/vB mempool fee rates, use estimate_bitcoin_mempool_fees'). Nothing about selection is left to inference.

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