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

With no annotations, the description carries the full burden and does so: it discloses the paid x402 model ($0.01 USDC on Base), that billing only occurs on a 200, and the error semantics (404 unknown id, 400 invalid args, 503 during data refresh). That is exactly the compensation needed for a bare schema.

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 and use case, then operational detail; nearly every sentence earns its place. The billing caveat is stated twice ("charged only for a 200" and "charged only for a successful answer"), which is minor redundancy.

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 single-parameter read tool with no output schema, the description covers purpose, id sourcing, pricing and failure modes. It stops short of describing the graph payload itself (node/edge shape, size, ordering), which is the one thing left for an agent to guess.

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 baseline is 3, and the description adds real value by naming the provenance of the id both externally (/api/v1/opportunities) and within this server (search_opportunities). It does not discuss the id pattern or format beyond what the schema already shows.

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?

"What one opportunity depends on: protocols, stablecoins and their issuers, oracles, bridges and vault curators, as a graph" names a specific resource, direction (outbound dependencies) and node types. That implicitly separates it from the reverse-direction sibling get_dependents, but no sibling is named explicitly.

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?

"Useful for finding hidden shared exposure before combining positions" gives a concrete scenario for reaching for this tool rather than a plain score lookup. It also tells the agent where to source the required id (search_opportunities inside this MCP server, or the free /api/v1/opportunities route), but it never names an alternative tool or states an exclusion.

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