get_xpts

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

Annotations already declare readOnly/idempotent/non-destructive, and the description goes further by disclosing methodology (season xG/xA/clean-sheet/save/bonus rates, expected minutes, fixture difficulty) and two real behavioral caveats (season-start noise, rotation blindness). It stops short of describing row shape or ordering guarantees, which keeps it from a 5.

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?

Two tight sentences: the core ranking behavior and methodology come first, filters second, caveats and the handoff last. No sentence is filler and the most decision-relevant caveat is not buried.

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 burden of explaining what comes back, and it does so at a high level (xPts estimate shown beside ep_next). It covers caveats and methodology well; only output ordering and the default row count remain unstated.

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 80%, so team, position and max_price are already documented in the schema; the description only restates 'Filter by position, team and max price' without adding format or interaction guidance. Neither gameweek defaulting behavior nor the limit cap is touched on in the description, so it adds little beyond the schema.

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 and resource ('Rank players by estimated expected points (xPts) for a gameweek') and names the data source (FPL API). The ranking framing plus the 'shown beside FPL's own ep_next' clause makes it clearly distinct from search_players or get_player_history.

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?

States both positive uses ('captain shortlists and finding transfer targets') and explicit limitations ('noisy early in the season and ignores rotation'). It also routes the agent to a specific sibling for the gap it cannot cover: 'cross-check availability with get_live_availability.'

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