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

With no annotations, the description carries the full disclosure burden and does well: it explains normalization to percent-of-close, the sign convention for offsets, and the important edge case that a moment inside the present has no 'after' (a silent truncation the agent would otherwise misread). It does not state the read-only nature explicitly or describe the shape/resolution of returned paths, 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?

The core purpose and the primary alternative are front-loaded, and each subsequent sentence adds a distinct rule (offset signs, present-moment truncation, the 24-moment cap, parameter roles). Slightly dense and could trim a clause or two, but there is no filler.

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 4-parameter, no-annotation, no-output-schema tool, the description covers purpose, routing, parameter meaning, limits, and a subtle truncation behavior. What remains unstated is what a returned path actually contains (point density, length, missing-data handling), which matters when paths are overlaid.

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 baseline would be 3, but the description adds real meaning the schema lacks: offsets are minutes relative to the moment with negative meaning before and positive after, `at` is capped at 24 UTC ISO-8601 moments, `scale` is the backward reach and `after_minutes` the forward reach, and `asset` must come from list_coverage. The only gap is no guidance on interaction between `scale` and `after_minutes` or default behavior.

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 concrete verb and resource ('Draw the price path around one or more moments') plus the transform ('as percent from the close at each') and why it exists ('so paths of different sizes can be laid over one another'). It explicitly separates itself from get_market_state (single-moment summary), find_analogs, query_history, and get_topic_outcomes, so an agent can pick 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?

Gives an explicit trigger ('when you already hold the moments... and want their paths side by side') and names three alternatives with the condition that selects each. It effectively tells the agent both when to use this tool and when to use a sibling instead.

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