fossil_age_overlap

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

With no annotations at all, the description carries the full behavioral burden. It discloses the core semantics (overlap of concurrent range zones, expressed in millions of years), which is the key trait, but says nothing about the result when taxa ranges do not overlap, how unknown or misspelled taxon names are handled, the intended stratigraphic timescale, or the shape and type of the returned value.

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?

One sentence, front-loaded with the verb and containing the output unit and input domain with zero filler. Every clause carries information an agent needs.

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 is the only behavioral source, and while it states the unit of the result it does not specify the return type or edge-case results. For a one-parameter calculation tool this is close to adequate, but the heavy jargon ("Concurrent Range Zone") is left undefined and failure modes go unmentioned.

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 single parameter has 100% schema description coverage including example values, so the baseline is 3. The description does add one piece of meaning not in the schema: the minimum of two taxa, which signals that a single entry is invalid input. It still does not clarify name-matching behavior (synonyms, case, taxa absent from the underlying dataset).

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 pairs a specific verb ("calculate") with a precisely named output ("chronostratigraphic Concurrent Range Zone overlap duration in millions of years") and its input domain (2+ index fossil taxa). Nothing about the operation is ambiguous, and the sibling tools (bullion_melt, specific_gravity, watch_beat_math, beam_deflection) are unrelated domains, so no disambiguation is required.

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 only implied by the domain framing: an agent can infer this is for stratigraphic range-overlap analysis on index fossils, and the description supplies the "2 or more" minimum as a hard condition. There is no explicit statement of when to prefer this over an alternative, no prerequisites, and no note on what to do with a single taxon or non-overlapping ranges.

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