Fund Position

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds the auth requirement, which is genuinely useful context not present in the annotations, but says nothing about response shape, data window semantics, or rate behavior.

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, front-loaded with the action, then auth, then parameter sourcing and format. No filler and nothing redundant.

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, single-entity query with no output schema, the description covers auth and the key parameter provenance. It could note the default window behavior or what the position detail contains, but nothing critical to correct invocation 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 description coverage is 100%, so counter_id format, start/end format and _jq are fully documented in the schema. The description only restates the date format and slightly extends the counter_id source list (adding fund_position_overview), so baseline 3 applies.

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 and resource ('Get one held fund's position detail') and implies single-fund scope, which separates it from the list-style siblings like fund_positions. It does not explicitly contrast itself with the many close relatives (fund_position_overview, fund_position_nav, fund_position_performance), so an agent must still infer the boundary.

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 clear routing context by naming the three tools that supply counter_id (fund_position_overview / fund_hot / fund_list) and marks start/end as optional. It stops short of explicit when-not guidance and does not clarify why one would pick this over fund_position_overview.

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