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

With no annotations, the description carries the full burden and does well: it discloses edge-case semantics (equal to prior high/low is NOT a take-out, first bar yields null) and enumerates the derived fields returned. It does not explicitly state that the operation is pure/read-only or what happens on malformed/insufficient bar data, which keeps it short of 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?

Front-loaded with purpose, then the decision rule, then secondary outputs, then the routing directive — every sentence carries content. Minor drag from jargon ('Truth #1', 'first_side data') that is never defined and slightly interrupts the flow.

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 single-parameter, no-output-schema tool, the description covers the classification rule, the null first bar, and names the extra returned fields. It stops short of giving the actual return object's field names/shape, so an agent still guesses at exact output keys, but the substance is sufficient to call it correctly.

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% and the bars parameter is fully documented (accepts objects or row arrays, t is bar START time, ISO 8601). The description only reinforces ordering via 'compare each bar with the bar before it', consistent with the schema's 'oldest first' but adding little beyond it. 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 ('Label every bar') plus the exact output domain (TheStrat scenarios 1, 2u, 2d, 3). It also declares the secondary outputs (color, hammer/shooter, failed-2 flags, 3u/3d), so the agent knows precisely what it gets back and can distinguish it from siblings like find_signals or potential_signals_next_bar.

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 closing directive 'Use this instead of reading a chart' gives a clear positive usage condition, and the labeling rule implies it applies to raw OHLC series. However, it never contrasts itself with the numerous sibling analysis tools (signals_in_force, find_signals, etc.), leaving the agent to infer which analysis entry point to pick.

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