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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds value by stating 'Free read' and explaining the economic backing relationship (every PerpsPad coin is backed by a leveraged perp position on one of these markets), which helps an agent understand what the data represents. The SAP MCP execution guidance about signer boundaries is generic boilerplate but adds context that hosted reads never receive keypair bytes.

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?

The core description is two sentences with concrete examples and a clear scope statement. The SAP MCP execution guidance block is somewhat repetitive with the schema description, but it's compact and front-loaded with the most important routing information (free, direct call). The description earns its place without excessive verbosity.

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 parameterless read tool with an output schema present, the description is nearly complete. It explains what the tool returns (markets with leverage caps), the use case (discovery), and the execution context (free, direct). The only minor gap is not describing the exact output shape, but the output schema exists and covers that. The sibling list shows many similar market tools, but the PerpsPad-specific naming and description disambiguate sufficiently.

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?

The tool has zero parameters, so there is no parameter semantics burden on the description. The schema description coverage is 100% (the schema itself contains the same SAP guidance text). The description appropriately focuses on what the tool returns rather than parameters, which is the right trade-off for a parameterless read tool.

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 states a specific verb ('List'), a specific resource ('PerpsPad supported underlying perp markets'), and adds concrete detail (leverage caps with examples like BTC 1-40x, SOL 1-25x). It also clarifies the relationship to PerpsPad coins ('backed by a leveraged perp position'), which distinguishes it from generic market-listing tools like sap_perp_markets or sap_backpack_get_markets.

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 clearly frames this as a read/discovery workflow and states it is free to call directly without x402. It doesn't explicitly name sibling alternatives or say when NOT to use this tool, but the read-only intent and free routing guidance give an agent enough context to select it appropriately among the many sap_* tools.

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