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

With no annotations, the description carries the full burden and discharges it well: it discloses the terms-lock once events exist, the stale-carry-math hazard, status auto-progression vs manual override, and the decimal-fraction unit convention. It omits auth/permission needs and reversibility, but the mutation hazards unique to this tool are clearly surfaced.

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-loads the operation and patch semantics, then layers the lock rule, the remedy, the status override, and the unit convention. Every sentence is load-bearing with 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 16-parameter mutation tool with no annotations and no output schema, the description covers the risky semantics an agent must know before calling. It leaves out error behavior on locked-field attempts and any permission requirements, but is otherwise sufficient.

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 is 3, but the description adds real meaning: it enumerates which fields are locked once events exist (principal, entryFee, entryFeePct, carryPct, hurdlePct, investmentDate, currencyCode) and reinforces that fee percentages are fractions in [0,1]. This cross-field conditional constraint is not expressible in the flat 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?

The opening sentence states a specific verb ('Update') and resource ('venture deal'), and 'Only provided fields change' clarifies the patch semantics. It is distinguishable from update_venture_event / update_venture_platform by resource name, though it never explicitly contrasts itself with those siblings.

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 actionable when-to-use context: 'Delete the events first if the user needs to fix terms' and 'Status can be overridden manually.' It explains the conditions under which locked fields become mutable, but does not name the alternative tool (update_venture_event) for editing events.

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