bpb_get_backpack

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 for the most important trait: it explicitly declares read-only behavior and that it does not trigger normalize or save writes, which is the key side-effect question for a game-state tool. It also discloses the return payload shape in detail. It stops short of mentioning cost, latency, or behavior on an empty/uninitialized backpack.

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 core verb and resource, followed by a compact enumeration and a one-clause side-effect disclaimer. The field list is dense but each entry carries real information rather than restating the name; a slightly tighter grouping of the counts would be the only improvement.

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?

There is no output schema and no annotations, so the description must carry the return contract and safety profile alone — it does both by enumerating every returned section and stating the read-only/no-normalize guarantee. Given a zero-parameter, zero-annotation tool, nothing an agent needs in order 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?

The tool takes zero parameters, so the baseline is 4 and there is no parameter meaning to add or omit. The description correctly implies a full-state dump with no filtering options, matching the empty 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?

States a specific verb (读取/read) and resource (完整背包布局/complete backpack layout), then enumerates exactly what is returned: bags with position/cells/shape/rotation, items with bag_id/floating/fusion_locked/sockets, grid, storage box, and aggregate counts. This is far more specific than the sibling read tools (bpb_get_state, bpb_get_phase) and lets an agent distinguish it without opening a schema.

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?

Usage is implied by the content enumeration and by '只读，不触发 normalize 或存档写入', which tells the agent this is the non-mutating read path versus the edit siblings (bpb_open_backpack_edit, bpb_edit_bags). However, no sibling is named and no condition is given for choosing this over bpb_get_state or bpb_get_star_slots, so the routing decision is left to inference.

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