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

Beyond the annotations (readOnlyHint=true, openWorldHint=true), the description discloses rich behavioral traits: keyless free-tier sources with optional API keys that raise rate limits, cache TTL of 5 minutes, a budget of 8s per source, and the exact signal detection logic (P0/P1/P2). It also mentions that EVM-compatible addresses are supported. No contradiction with annotations exists.

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 description is long but well-structured with clear sections for modes, signal detection, sources, and env vars. It is front-loaded with the primary purpose and then proceeds logically. Some content (e.g., the mode list) overlaps with schema descriptions, but the additional detail on signal detection and sources earns its place. It is appropriately sized for a complex multi-mode tool.

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?

Given the tool's complexity (5 modes, 6 chains) and the presence of a rich output schema, the description is remarkably complete. It explains supported chains, data sources, rate-limit behavior, cache TTL, performance budgets, and compliance signal logic. The async parameter and chain behavior are covered by the schema, so no gap remains. The description provides all necessary context for an agent to select and invoke this tool 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?

The input schema already covers all parameters (100% coverage), so the baseline is 3. The description adds substantial meaning beyond the schema by detailing the output fields for each mode, e.g., 'wallet_profile' includes 'type (EOA/contract/CEX/protocol), inferred persona (whale/MEV-bot/DeFi-user/hodler…)', and 'pnl_estimate' includes 'confidence rating (high/medium/low)'. This enriches the semantics of the 'mode' parameter beyond the schema's one-line descriptions.

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 the tool's purpose: 'Multi-chain on-chain analytics for crypto trading agents, on-chain analysts, AML/compliance teams and DeFi BD.' It names the specific chains (Ethereum, Base, Polygon, BSC, Arbitrum, Optimism) and enumerates five distinct modes (wallet_profile, token_flows, pnl_estimate, counterparties, defi_positions), each with a brief explanation. This specificity distinguishes it from sibling tools like kyc_screener or x402_payment_flow_analyzer, which target different analytics.

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 provides clear usage context by listing target audiences (trading agents, analysts, AML/compliance, DeFi BD) and describing the signal detection levels (P0/P1/P2) that trigger compliance alerts. It also notes that the 'all' chain option is slower (~30s). However, it does not explicitly state when NOT to use this tool or name alternative sibling tools for comparison, so it stops short of full exclusion guidance.

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