get_portfolio_history

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 richly: it discloses credential requirements, a 5x rate-limit cost with concrete budget impact ('remaining drops by ~5'), the per-window cadence/capacity table, oldest-first ordering, deposit-neutral PnL semantics, and monotonic volume.

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 the deprecation notice, then the description. It is dense and fairly long, but nearly every sentence conveys behavior an agent needs; the cadence table and rate-limit detail are load-bearing rather than padding.

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 read-only history tool with no output schema, the description covers scope, return semantics, ordering, window trade-offs, cost, and auth — nothing an agent needs to call it correctly 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?

Schema coverage is 100%, so the baseline is 3, but the description adds real meaning beyond the schema by giving the concrete cadence/capacity values per window (day 5m/288, week 1h/168, etc.) that the window enum description only alludes to.

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?

States a specific verb+resource (get portfolio time-series) and enumerates exactly what it returns (equity, cumulative trading PnL, cumulative traded volume). It explicitly positions itself against siblings fetch_portfolio_history and fetch_equity_history, so an agent can route without opening schemas.

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 very first clause routes the agent away from this tool ('Deprecated: use fetch_portfolio_history'), which is the strongest possible when-not guidance. It also names fetch_equity_history as the narrower alternative and warns to poll sparingly.

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