compute_session_profile

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states non-actions ('does not change the chart, optimize session definitions, or make a trade recommendation') and discloses a data quality caveat: volume is 'clearly labelled as unverified tick-or-exchange volume.' It also specifies use of closed minute bars and deterministic profiles. It does not mention side effects like API-side computation cost or rate limits, but the main behavioral traits are transparent.

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 description is four sentences, each earning its place: the main purpose, timezone/boundary support, the list of computed outputs, and explicit non-goals. Key qualifiers like 'deterministic,' 'closed minute bars,' and 'one exact TradingView chart' are front-loaded. No filler or repetition is present.

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?

Given the tool's complexity (7 parameters, no output schema), the description lists the major return components—coverage, OHLC range, return, opening-range extension, high/low timing, VWAP, PDH/PDL/PDC reactions, and volume—which gives an agent a good sense of what to expect. It also clarifies that observation limits apply only to returned sessions while aggregates use all rows. It does not provide a precise output structure, but for invocation purposes it is reasonably complete.

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 71%, so the schema already documents most parameters. The description adds meaning beyond the schema by explaining session semantics: caller-specified IANA timezones, daylight-saving and cross-midnight boundary support. It also maps to outputs like 'opening-range extension' (relating to opening_range_bars) and 'coverage' (relating to minimum_coverage). This extra context enriches parameter understanding without being redundant.

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?

The description begins with a specific verb-resource pair: 'Summarize deterministic session-day profiles from closed minute bars on one exact TradingView chart.' This clearly distinguishes it from sibling tools like get_ohlcv or compute_market_regimes. The scope is explicit via 'one exact TradingView chart' and 'deterministic,' making the tool's purpose unambiguous.

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 description conveys clear usage context: analyzing session-day profiles with caller-specified IANA timezones, daylight-saving, and cross-midnight boundaries. It also states exclusions—'does not change the chart, optimize session definitions, or make a trade recommendation'—which helps agents understand what not to expect. However, it does not name specific sibling tools to use as alternatives for those excluded tasks.

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