CME futures positioning (weekly COT report, BTC + ETH)

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

Beyond the readOnlyHint annotation, the description adds valuable behavioral context: data source (official CFTC), update frequency (every Friday), and an important interpretation caveat about hedge fund shorts being basis trades. This helps the agent understand the data's nuance and reliability.

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 compact—three sentences that front-load the call instruction, then detail the return contents, and end with a note. Every sentence serves a purpose with no 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?

Even without an output schema, the description names the specific data returned (net positions, week-over-week changes, open interest, extremes/streaks) and the source/update cycle. This is sufficiently complete for an agent to invoke the tool and interpret results 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 tool has zero parameters, so the schema is empty. The description compensates by stating the scope (BTC and ETH CME futures) and the output dimensions, adding meaning beyond the bare schema. Baseline 4 for zero params is appropriate.

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 identifies the tool's function: retrieving CFTC Commitments of Traders positioning data for Bitcoin and Ethereum futures. It distinguishes itself from sibling tools (e.g., get_etf_flows, get_open_interest) by focusing specifically on trader categories and the weekly COT report.

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?

It explicitly states when to call: 'when the user asks how hedge funds or institutions are positioned in Bitcoin or Ethereum, or about the CFTC Commitments of Traders report.' This provides a direct trigger and implicitly differentiates it from alternatives like total open interest or ETF flow tools.

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