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

Annotations already cover read-only/idempotent safety, but the description adds genuinely non-obvious behavior: trade_volume is in outcome SHARES not USD, the call always returns exactly one row, and a never-recorded token returns all zeros with total_events = 0 meaning 'never recorded' rather than 'quiet'. That last point prevents a real misinterpretation.

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?

A single dense paragraph with zero filler: scope first, then returned metrics and units, then input provenance and the failure mode. Every clause carries information an agent needs before calling.

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 no output schema, the description carries the return-shape burden and does so: it names the returned fields, their units, the row count guarantee, and the empty-result semantics. For a one-parameter read tool with full annotation coverage, nothing material is missing.

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?

Although schema coverage is 100%, the description goes well beyond it: it identifies the id as an ERC-1155 OUTCOME token id in decimal string form, names the two sibling tools where it can be found, and warns that a 0x condition_id will fail. The schema only says 'outcome token id (decimal string)'.

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?

Opens with a specific verb+resource+scope: 'Tape summary for ONE Polymarket outcome token', then enumerates exactly which metrics are returned (total_events, trades, trade_volume, snapshots, first_ms/last_ms). This makes it clearly distinct from the sibling polymarket_tape (event-level) and polymarket_ohlcv (price bars).

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 concrete guidance on obtaining the required token_id (clob_token_ids in polymarket_market_detail, outcomes[].token_id in polymarket_markets) and explicitly rules out a wrong input ('a condition_id (0x...) will NOT work'). It does not, however, say when to prefer this over polymarket_tape or polymarket_market_detail, so the alternative routing is implied rather than stated.

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