tablaze

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

The description goes well beyond the annotations: failed postconditions keep effects and set replan_required, the batch stops on first failure, popup redirects skip post_checks, cancellation closes the session but retains effects, and click_xy coordinates lack DOM identity guards. This is exactly the behavioral context an agent needs beyond readOnlyHint/destructiveHint/openWorldHint.

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 dense and information-rich with no filler, and it fronts the core action-execution purpose. However, it reads as one long run-on paragraph rather than structured guidance, which slightly reduces scannability for an agent needing to quickly extract key constraints.

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—14 action variants, post_checks, snapshot refs, timeouts, popups, and cancellation—the description covers nearly all behavior an agent needs to call it correctly. It even explains effect persistence, failure semantics, and coordinate caveats. The only minor omission is a detail about include_snapshot, but that is not essential for correct invocation.

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 very low at 14%, but the description compensates with meaningful semantics: post_checks reference the same snapshot's refs and poll for async outcomes, click_xy is in main-viewport CSS pixels, fill_secret uses an alias from snapshot.available_secrets, and action budgets/timeouts are specified. It does not explain every parameter (e.g., include_snapshot) or every action type, but the schema covers the structural constraints and the description adds the critical runtime semantics.

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 uses a specific verb ('Execute') and clear resource ('ordered actions against a current snapshot'), and immediately distinguishes tab_act from tab_verify by routing navigation-dependent checks elsewhere. It leaves no doubt about what the tool does.

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?

It explicitly says 'use separate tab_verify after navigation' and instructs using fill_secret with an observed ref and a snapshot secret alias, giving concrete when-to-use guidance. It also clarifies that post_checks are the in-call verification mechanism, with separate timeout semantics, which helps the agent choose between this and sibling verification tools.

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, openWorldHint, and destructiveHint. The description adds meaningful behavioral context by warning that images can contain visible page data and clarifying that full-page capture requires explicit request. This goes beyond the annotations without contradicting them.

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?

Three sentences with no filler: core behavior is front-loaded, the privacy warning is valuable, and the return type is stated. Every sentence 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 two-parameter capture tool with no output schema, the description covers the key operational details: default scope, full-page opt-in, output type, and data-visibility risk. It lacks an explicit comparison to tab_snapshot and precise output encoding, but it 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?

The schema documents session_id but leaves full_page with only a type. The description compensates partially by indicating that full-page capture happens only when explicitly requested, implying the default is viewport-only. However, it does not name the parameter or explain its format beyond that implication.

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 clearly names the action ('Capture') and the resource ('current viewport' or 'full page'), and states the output ('image and URL metadata'). It is specific enough to distinguish it from status/navigation tools, though it does not explicitly differentiate it from the similarly named sibling tab_snapshot.

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?

There is no guidance on when to choose this tool over tab_snapshot, tab_extract, or other siblings, and no exclusions or alternative routing. The 'when explicitly requested' note is about the full_page parameter, not about tool selection, so it does not satisfy the usage-guideline dimension.

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 include destructiveHint=true, but the description adds valuable behavioral context by warning that 'Unsaved changes in that session are lost.' It also clarifies the side effect of releasing resources, which goes beyond what the annotations alone convey.

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 short sentences, front-loading the action and then adding the critical data-loss warning. Every word contributes value, with no repetition of the title or schema.

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 one-parameter destructive tool, the description covers the target resource, the resource-release effect, and the key risk of unsaved data loss. It does not describe error behavior or return value, but the simplicity of the operation and the presence of annotations make this a minor gap.

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 schema fully documents session_id as a required string 'returned by tab_open,' so schema_description_coverage is 100%. The tool description adds little parameter-specific meaning beyond reinforcing that the session is owned by this server. Baseline 3 is appropriate.

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 uses a specific verb and resource: 'Close one session owned by this server and release its resources.' This clearly distinguishes tab_close from sibling tools like tab_open, tab_state, and tab_act. The object of the operation 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 context is implied rather than explicit: closing a server-owned session and releasing resources suggests this tool is for cleanup/termination. However, it does not explicitly state when to use it versus alternatives or mention any exclusion cases, leaving some inference to the agent.

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 mark destructive and open-world behavior; the description adds valuable context beyond that: one-shot nature, unarmed dialogs dismissed and reported as unsupported flow, and advice to check actual outcomes before retrying.

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?

Three sentences, front-loaded with the primary purpose, then behavioral notes. Every sentence earns its place without 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?

Covers the arm-before-dialog workflow, one-shot semantics, and unarmed fallback. However, with no output schema, it does not describe return values or what happens if no dialog appears, so not a perfect 5.

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 documents only session_id; the description compensates for low coverage by explaining prompt_text is entered only for prompt dialogs and action is a single accept/dismiss choice. It does not add further session_id semantics.

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 the specific verb 'Arm' and resource 'accept or dismiss response' for native dialogs, clarifies scope with 'alert, confirm or prompt'. It clearly distinguishes from sibling tools like tab_act by focusing on one-shot dialog handling.

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?

Explicitly says to use it 'before the action that opens an alert, confirm or prompt', providing clear timing and context. It does not name alternatives explicitly, but the usage context is unambiguous.

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 mark the tool read-only and non-destructive. The description adds valuable behavioral detail beyond annotations: completed results include an owned local path, pending is not completed, failed downloads set isError, and files persist after session close. No contradiction with annotations.

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?

Four compact sentences deliver all essential behavior with no repetition or filler. The main listing action is front-loaded, and each following sentence adds distinct information.

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, so the description carries the burden of explaining what results look like. It covers completion, pending, failure, artifact paths, and file persistence. It could be slightly more explicit about the exact status representation, but an agent can reasonably invoke the tool correctly with this 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?

Schema coverage is only 33%, so the description must compensate for download_id and timeout_ms. It does: 'Supply download_id to wait up to timeout_ms for completion' explains both parameters' roles. It does not mention defaults or whether timeout_ms is ignored without download_id, but the core semantics are covered.

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?

Description states a specific action ('List downloads created by this session') and supports optional waiting on a particular download. It clearly identifies the resource and scope, and no sibling tool overlaps with this purpose.

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 invocation context: omit download_id to list, supply download_id to wait up to timeout_ms. It does not explicitly name alternatives or exclusions, but no sibling appears to compete, so the guidance is sufficient.

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 this as read-only and non-destructive, and the description's 'Read' aligns with that. It adds useful behavioral context beyond annotations by disclosing that results may be bounded and that truncation information is returned when the result is limited.

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, front-loaded sentence with no filler: it states the core action, the data types, the optional selector, and a key return behavior. Every phrase earns its place, though 'bounded' is slightly ambiguous.

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 tool with no output schema, the description covers the main capability and truncation behavior but omits important operational details such as how max_items applies to different kinds, what table extraction returns, and whether a default selector covers the whole page. It is adequate but has clear gaps.

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 low (25%), but the description adds meaning by naming the kind enum values ('text, links or table data') and mentioning the optional CSS selector. It does not clearly explain the semantics of max_items beyond the vague word 'bounded', nor does it describe the output shape for each kind.

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 uses a specific verb ('Read') and names concrete resources: bounded text, links, or table data, optionally scoped by a CSS selector. It clearly conveys what the tool does, though it does not explicitly differentiate itself from the similar sibling tab_extract_structured.

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: call this when you need to read text, links, or tables from a page, possibly within a selector. However, it gives no explicit when-to-use vs alternatives guidance, nor does it mention cases where a sibling like tab_extract_structured or tab_find would be more appropriate.

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?

Beyond the read-only and non-destructive annotations, the description adds meaningful behavioral detail: hard limits (30 fields, 20 matches per field, 100 total), explicit rejection of hidden/password/truncated evidence, and the guarantee that no model or inference is used. This gives an agent a strong, accurate picture of what will and won't happen.

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 dense and efficient: the core action and return value are front-loaded, followed by supported modes, limits, and explicit non-behaviors. Every sentence conveys essential operational information without fluff or repetition of schema details.

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 description is sufficiently complete for a 3-parameter tool with no output schema: it explains what is returned (per-field source URL, selector, quote provenance), what constraints apply, and what is rejected. An agent can reasonably decide whether to call it and understand the expected result.

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 only 33%, so the description must compensate. It does: it clarifies that 'fields' can use text, attribute, and value modes, supports typed scalars/arrays, and imposes field-count limits. It doesn't explain the 'required' or 'multiple' flags explicitly, but the schema already enumerates those and the description's added semantics are useful.

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 ('Read'), a precise resource ('named fields from observed DOM using selectors'), and the differentiating value-add: JSON Schema draft-07 validation and per-field provenance. This clearly separates it from siblings like tab_extract and tab_find by emphasizing schema validation, typed extraction, and evidence provenance.

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 when to use this tool: when you need schema-validated, selector-based field extraction with provenance, and not when you need model-based inference ('Does not call a model or infer missing facts'). It does not explicitly name alternative sibling tools or contrast them, but the context is clear and the exclusions (hidden/password controls, truncated evidence) are stated.

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?

The description discloses side effects (changes scroll position) and non-actions (does not click or submit), which aligns with destructiveHint=true and readOnlyHint=false. It also explains the bounded step search and the fresh snapshot return, adding valuable context beyond the annotations.

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?

Three focused sentences, front-loaded with the core action, followed by specific usage details, then a side-effect note. No redundancy or unnecessary elaboration.

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?

Covers core behavior, return format (fresh snapshot with refs), side effects, and a key interpretation caveat about found:false. Missing explicit detail on timeout_ms/max_scrolls defaults and the exact output structure, but given the annotations and the description, it is reasonably complete for a search tool.

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?

With only 29% schema coverage, the description compensates partially by explaining the container_ref/snapshot_id relationship for virtual lists and implying max_scrolls via 'bounded steps'. However, other parameters like timeout_ms, frame_id, and text receive no additional meaning, leaving gaps for the agent.

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 clearly states the action (search for visible text) and the resource (current frame), with specific scrolling behavior. It distinguishes itself from sibling tools like tab_extract or tab_verify by focusing on text discovery and returning a snapshot with actionable refs.

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?

Provides explicit guidance for virtual lists (use container_ref with current snapshot_id) and clarifies the semantics of found:false, which helps the agent interpret results. However, it does not explicitly name alternative tools or state when not to use this tool, so it falls short of a 5.

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?

With readOnlyHint and destructiveHint already covering safety, the description adds non-obvious behavioral facts: this operation does not launch a browser and does not discover unrelated user tabs. That goes beyond the annotations and clarifies the tool's limited scope.

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?

Two short sentences with no filler. The positive statement comes first and the behavioral exclusions are packed into a second sentence that 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 parameterless, read-only listing tool with annotations covering safety, the description is sufficient: it states the returned resource and the key non-behaviors. No output schema exists, but the absence of parameters makes the call surface fully clear.

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 tool takes zero parameters and schema coverage is 100%, so there is no parameter documentation burden for the description. The baseline of 4 applies; no additional parameter semantics are 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 names a concrete action and resource ('List the sessions owned by this server') and adds negative scope ('Does not launch a browser...'), making the intent unambiguous. It is not a restatement of the title or name, and it differentiates from tab-discovery tools.

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?

It gives a clear context: use when a server-owned session listing is needed, and it explicitly excludes browser launching and unrelated user tab discovery. It stops short of naming an alternative sibling tool (e.g., tab_tabs), so the when-not is implicit rather than pointing to a specific replacement.

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 mark the tool as unsafe and destructive, and the description adds meaningful behavioral detail: cookies and tabs are retained, navigation returns a fresh snapshot, and previous references become invalidated. This goes beyond the annotation flags and clarifies the real-world side effect of using the tool.

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?

Two sentences carry the full purpose, supported actions, and key behavioral consequence with no filler. The most important scoping fact ('existing session') is front-loaded, and the invalidation warning is compactly placed.

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 navigation tool with no output schema, the description covers the essential semantics: what the tool does, which actions are supported, what is preserved, and what happens to prior snapshots. It is slightly incomplete on url semantics and route selection versus sibling tools, but it gives enough for a confident call.

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?

With only 33% schema description coverage, the description should compensate for undocumented parameters, especially url. It mostly restates the action enum already present in the schema and does not explain how url applies (e.g., that it is required for goto and irrelevant for back/forward/reload). The description adds little parameter-level meaning beyond the 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 description states a specific action ('Navigate') with a clear resource: an existing session's current tab, and enumerates the supported operations (goto, back, forward, reload). It is distinct from sibling tools like tab_open, which creates a session, by anchoring usage to an already-existing session.

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 'within an existing session' provides clear context for when this tool applies, implying it should be used after a session has been created rather than to create one. It does not explicitly name alternatives or state when not to use it, so it stops short of a 5.

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?

Beyond the annotations (readOnlyHint=false, openWorldHint=true, destructiveHint=true), the description discloses cancellation semantics, cleanup of late-created pages, session isolation, and that the browser stays warm. This is rich, non-obvious behavioral detail that helps an agent predict side effects and manage resources. No contradiction with annotations.

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?

Three sentences, each earning its place: the first states the core action and output, the second explains cancellation behavior, and the third sets performance expectations. Information is front-loaded and there is no filler or repetition of schema data.

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 tool with no output schema, the description covers the main behaviors: new session, snapshot return, cancellation cleanup, session isolation, and warm browser. The 'compact full snapshot' phrase is somewhat generic and does not specify the snapshot's structure, but combined with annotations the essential context is present.

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 50%: storage_state is described in the schema, while url is not. The description adds some meaning to url by specifying 'HTTP(S) page' and implies session context, but it never mentions storage_state or its role. The schema description covers storage_state, so overall the agent can understand both parameters, but the tool description itself adds only partial compensation for the low schema coverage.

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 action ('Open an HTTP(S) page'), a specific resource ('in a new session'), and what the tool returns ('a compact full snapshot'). It is clear and unambiguous. However, it does not explicitly contrast with sibling tools like tab_navigate or tab_tabs, though 'new session' implicitly points to a distinction from operating on existing tabs.

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 clear contextual guidance: this tool opens a page in a new session, and cancellation cleans up the attempt without closing sibling sessions or the shared browser. This tells the agent the tool is appropriate for isolated, temporary page opens. It lacks explicit when-not-to-use instructions or named alternatives, but the context is strong.

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 indicate readOnly=false, destructiveHint=true, and openWorldHint=true. Beyond those, the description adds valuable context: the artifact is private and local, files survive closing, and print layout may differ from screen layout. This gives the agent important expectations about side effects and output fidelity without contradicting the annotations.

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?

Three short sentences, each earning its place: the first states the core operation and outputs, the second notes persistence, and the third warns about layout fidelity. The most important information is front-loaded, and 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?

With no output schema, the description properly explains the return values: path, SHA-256, and source URL. It also covers persistence and the layout caveat. Missing details are limited to parameter defaults or behavior for format/landscape, which are partially inferable from the enum schema.

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 only 33%, with only session_id documented in the schema. The description does not mention format or landscape at all, so the agent gets no guidance on how to choose A4 vs Letter or when to set landscape. With low schema coverage, the description needed to compensate for these parameters but did not.

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 uses a specific verb ('Print') and a specific resource ('the active page ... into a private local PDF artifact'), and clearly states what is returned: path, SHA-256, and source URL. This clearly distinguishes it from sibling tools like tab_capture or tab_snapshot, which are more likely screenshots or structured captures.

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 makes the basic use case clear: export the active page to a PDF. However, it does not explicitly name alternatives or say when not to use this tool, even though siblings like tab_snapshot, tab_extract, and tab_capture exist. The guidance about print layout differing from the screen is useful but is more behavioral than usage-routing.

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 mark the tool read-only, and the description adds meaningful context beyond that: changing scope resets the diff baseline, and secrets handling exposes only aliases, never values. The instruction to 'Respect truncation and frame metadata' is useful but slightly terse.

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?

Five compact sentences, with the core action front-loaded. Scope guidance, the diff-baseline caveat, truncation/frame caution, and secret-handling behavior are all relevant, and 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?

With seven parameters, low schema coverage, and no output schema, the description must supply substantial context. It covers scope selection and diff behavior well, but leaves full/diff mode semantics and the return payload largely implicit. Adequate with clear gaps.

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 only 14%, so the description carries most of the parameter burden. It adds real meaning for selector and viewport_only, and hints at frame_id via frame metadata, but it never explains the mode full/diff choices, text_limit, or max_elements. This is partial compensation, not full.

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 'Read the page and mint a new snapshot_id', which is a specific action with a distinct output resource. It does not explicitly name a sibling alternative, but the snapshot_id concept and scope language make the tool's role clear.

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?

It gives concrete selection guidance: use a CSS selector for a root or viewport_only to reach controls beyond a truncated page. It also warns that changing scope resets the diff baseline, which is useful when deciding scope. It does not explicitly compare against sibling tools or state when not to use it.

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?

Beyond the annotations, the description adds meaningful behavioral details: data is stored privately, may contain credentials, is not returned to the model, and explicitly excludes sessionStorage, extensions, and open tabs. This is valuable context for a write operation and does not contradict the annotations.

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 concise sentences with no filler. The core behavior is front-loaded, and the key exclusions and security caveat are packed efficiently into the second sentence.

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 single-parameter tool with a straightforward write-side purpose, the description covers what is saved, where, the security implication, and the consumer of the saved state. No critical invocation information is missing even without an output schema.

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 only parameter, session_id, is already fully documented in the schema as 'Session ID returned by tab_open.' The description adds no additional parameter-level detail, so the baseline of 3 applies given 100% schema coverage.

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 action ('Save'), specific resources ('cookies, localStorage and IndexedDB'), and the destination ('private local artifact file'). It also defines the downstream purpose ('later tab_open storage_state import'), which clearly distinguishes this tool from snapshot/extraction 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?

The intended use case is clearly stated: preserve browser authentication state for a later tab_open import. It does not explicitly list alternatives or when-not-to-use conditions, but the stated purpose gives enough context for an agent to select this tool over reading/extraction tools.

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=false, openWorldHint=true, and destructiveHint=true, so the description doesn't need to restate those. It adds valuable behavioral context: popups stay open and appear in snapshots, switching is required to work in them, and closing the last tab closes the session. This goes beyond the annotations and helps the agent understand side effects.

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?

Three sentences, each carrying distinct information: the action scope, the popup behavior, and the session lifecycle. No filler or repetition of schema details. The most important usage constraint (popups) is front-loaded.

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 multi-action tool with no output schema, the description covers the key behavioral nuances: popup handling, session scoping, and session closure. It doesn't describe return values or error conditions, but the action enum and parameter names give a reasonable picture. The missing parameter-to-action mapping is a minor gap, but the description is otherwise complete enough for an agent to invoke it 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 only 25% (only session_id has a description). The description does not explain the meaning of url, tab_id, or the action enum values beyond the enum itself. It implies that 'new' likely needs a url and 'switch'/'close' need a tab_id, but it doesn't explicitly map parameters to actions. Baseline 3 is appropriate because the description adds some context but doesn't fully compensate for the low schema coverage.

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 clear verb set ('List, open, switch or close tabs') and a specific resource ('tabs within a session'), and it distinguishes itself from sibling tools by noting that only this session's pages are accessible. It also clarifies the popup behavior, which is a unique trait not evident from the name or 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?

The description gives explicit context: popups stay open and appear in snapshots, and you must switch explicitly to work in them. It also states that only this session's pages are accessible, which implies when to use this tool versus other tab tools. However, it does not explicitly name alternative tools or say when not to use this tool, so it falls just short of a 5.

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?

The description adds significant behavioral context beyond the readOnly/openWorld/destructive annotations: snapshot validity can expire after a newer snapshot or document change, text assertions operate on visible page text rather than raw form values, and a successful click does not guarantee a successful outcome. These are non-obvious semantic details that materially affect how the tool should be used.

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, front-loaded with the core purpose, and every sentence carries useful operational information. It avoids repeating schema constraints and packs the most important caveats into a compact, readable form.

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 tool with nested check variants and snapshot-semantics, the description is almost complete: it covers assertion count, value-check ref/selector rules, snapshot staleness, and text-check scope. It does not describe the return shape or pass/fail format, but the tool's purpose as an assertion checker makes the outcome type fairly inferable, so the gap is minor.

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?

With only 50% schema description coverage, the description compensates by clarifying key parameter behaviors: exactly one observed ref or CSS selector for value checks, the snapshot_id requirement tied to refs, and the visibility semantics of text checks. It does not enumerate all six check kinds, but the schema already provides the const values and the description adds meaning beyond the raw property definitions.

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 a specific verb and scope: 'Check 1–20 explicit assertions,' which clearly identifies this as a verification tool for browser outcomes. It enumerates concrete behaviors (value checks, text checks, visibility) that distinguish it from snapshot/find/act siblings. It is not a tautology and directly supports the title's 'Verify browser outcome.'

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 actionable when-to-use guidance: use kind:value for current form element values, use the current snapshot_id when a ref is needed, and understand that text checks exclude raw form values. It does not explicitly name sibling alternatives or say when not to use the tool, but the usage context is clear enough for an agent to invoke it correctly after a browser action.

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