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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds a non-obvious behavioral nuance: filters are exact matches, not authorization boundaries, which clarifies that results are not permission-scoped. This goes beyond the annotation hints.

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 a single sentence with two clauses, front-loading the action and adding a critical caveat. It contains no filler or repetition.

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?

The tool has an output schema, so return format is covered elsewhere. It has four optional parameters, and the description provides a key nuance about filters but does not explain limit/cursor pagination or the meaning of project/source_id beyond their names. Given the low complexity and the presence of an output schema, the description is adequate but not 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 0%, so the description carries full responsibility for explaining parameters. It only states that filters are exact matches, which applies to project and source_id but not to limit and cursor. The parameter names are somewhat self-explanatory, but pagination semantics and data types are not clarified.

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 opens with 'List sessions', a clear verb and resource, and adds a clarifying note about filter semantics. It doesn't explicitly differentiate from sibling tools like history_search or history_read, but the core purpose is 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 implies usage: use this to list sessions with exact-match filters. The warning that filters are not authorization boundaries hints at when not to rely on it for security scoping, but no alternatives are named and no explicit when-to-use/when-not-to-use guidance is provided.

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

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint, so the safety profile is covered. The description adds meaningful behavior beyond annotations: events are returned complete, in snapshot order, and with pagination. It does not discuss errors or rate limits, but the added context is sufficient for this simple read operation.

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 compact sentence with no filler. It front-loads the verb and resource, then efficiently packs completeness, ordering, and pagination. Every phrase earns its place.

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 simple read-only paginated fetch with an output schema and comprehensive annotations, nothing critical is missing: session ID, record completeness, ordering, and pagination are all explicitly present. The tool's complexity is low, and the definition covers the full call contract.

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 0%, so the description must compensate. It covers session_id ('opaque session ID') and pagination (limit/cursor), giving high-level semantics for the parameters. However, it leaves details unstated, such as whether the cursor itself is opaque or how limit interacts with pagination. The schema's defaults and titles fill in some meaning, so the description is adequate but not exhaustive.

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 ('Read'), a clear resource ('complete events'), and the key differentiator ('by opaque session ID'), plus ordering and pagination. This distinguishes it from siblings like history_list and history_search, which imply broader listing or searching rather than a direct session-based read.

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 gives clear context for when to use the tool: when you have a session ID and need the full event sequence in snapshot order. It does not explicitly name alternatives or exclusions, but the intended use case is evident from the wording and sibling names.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, which cover the safety profile. The description adds meaningful behavioral context beyond annotations: 'Previews may truncate' discloses output truncation, and 'history_read returns full text' points to a workaround. This is valuable non-obvious information that aids agent decision-making.

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 two sentences long, with no fluff. The primary purpose is front-loaded in the first sentence, and the behavioral caveat and alternative are in the second. Every word serves a function, making it highly efficient and easily parseable by an agent.

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 that the tool has 5 parameters with 0% schema coverage and no parameter descriptions from the tool definition, the description is severely incomplete for correct invocation. It does not explain how to structure a query, handle pagination via cursor, or use project/source_id filters. The output schema exists, so return format isn't a concern, but the input semantics are under-documented. An agent would likely need to guess or rely on external knowledge to use this tool 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 description coverage is 0% – the input schema has no descriptions for any of the five parameters. The description fails to compensate: it does not explain the meaning or usage of query, limit, cursor, project, or source_id. While parameter names like 'query' and 'limit' are somewhat self-explanatory, the description adds zero value in clarifying parameter semantics, and the cursor/project/source_id fields remain ambiguous.

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 states a specific verb ('Find') and a specific resource ('literal Unicode text'), which clearly indicates a text search operation. This distinguishes it from the sibling tools history_sources (list sources), history_list (list history), and history_read (read full content). However, it does not explicitly name the target as 'history entries', though the tool name and sibling context imply that.

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 provides an implicit usage context: use this tool to find literal text, and use history_read to get full text when previews truncate. It explicitly mentions a condition to switch to an alternative, but it does not contrast against history_sources or history_list, nor does it state when not to use this tool. The guidance is partially useful but not comprehensive.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds that it lists coverage, revision, and timestamps, and clarifies it is not live discovery, which provides additional behavioral context beyond the annotations. This is useful and consistent.

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 a single, compact sentence that front-loads the core action and resource. Every word earns its place, and the clarifying 'not live discovery' adds meaningful distinction without waste.

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 zero-parameter tool with a clear output schema (not shown but noted), the description is complete. It states what the tool does, what it covers, and explicitly rules out live discovery. The distinction from siblings is clear, and an agent can correctly invoke it without additional information.

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?

There are zero parameters, so schema description coverage is trivially 100%. With no parameters, the description carries no burden to explain them, and the baseline of 4 applies. No additional param info is needed.

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 states a specific verb ('List') and resource ('imported source coverage, revision and timestamps'), and explicitly adds 'not live discovery' to distinguish it from live discovery tools. This differentiates it from siblings like history_list, history_search, and history_read, which are about different operations.

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 phrase 'not live discovery' clarifies that this tool is for imported/historical data, not real-time discovery. While it doesn't explicitly name alternatives, the context of the siblings (list, search, read) implies when this tool is appropriate. It gives clear context but no explicit exclusions beyond the live discovery caveat.

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